Ultralight bivy. Standard features: See full list on outdoorgearlab.

Ultralight bivy. Ultralight Bivy: Our original bivy we've been making since 2011, upgraded over the years. Sep 7, 2017 · This item: Sierra Designs Backcountry Bivy Bag for Backpacking, Camping, Bikepacking and Mountaineering, Ultralight, Minimalist Waterproof/Breathable Top Fabric Mountain Laurel Designs: MLD Gear is the most super ultra light backpacking gear and wilderness equipment available anywhere. Our goal with the MLD Bug Bivy was to design the lightest fully enclosed bug protection available that could be clipped under a tarp, or used under any single wall tent, tarp, poncho or pyramid style shelter. We've also braved swarms Feb 16, 2024 · The best bivy sacks provide shelter from the elements for the absolute minimum weight and time penalty. Bivy sacks only have a few real distinguishing features to help you choose. Standard features: See full list on outdoorgearlab. Includes info about materials, construction and designs. Shop our quality range of lightweight hiking swags / tents online for fast delivery Australia wide. Bivy Guide - Everything you need to know about bivy bags from Swami This is super nice article by Swami u/camhonan that tells you literally everything about bivy bags! Buy Waterproof Camping Flys, Tarps & Bivy Bags Online; Swags, Water-proof Hooped Bivy Shelter, Bivy Bags, Lightweight FlyTarps, Camo Tarp Fly Tents - the Ultimate Waterproof Light-Weight Highly Portable Outdoor Shelter systems for Australian conditions and travel Mar 21, 2024 · The Pro Bivy is a no-frills, lightweight shelter tailored for experienced ultralight backpackers. Despite this, they offer much the same performance and value of traditional ultralight hiking tents. 7 oz no-see-um netting and a 1. It comes in a number of different configurations. 9 inch handbag Large Space and Breathable Mesh: This ultralight tent for backpacking is specially designed for one person, but it is spacious enough and very breathable. Ultralight Bivy Tent for Single Person Bivy tents offer ultimate freedom in minimalist camping. Constructed of weatherproof yet breathable fabric, the Pro Bivy protects from wind and rainfly while reducing inner condensation. They're the minimum amount of material needed to keep you comfy and dry in just about any conditions. The term “bivy sack” derives from the source word, bivouac – meaning a temporary shelter – and brands and people abbreviate this in different ways; in the UK you are likely to see “bivvy Shop for Ultralight Bivy Sacks at REI - Browse our extensive selection of trusted outdoor brands and high-quality recreation gear. Standard features: - 1. Bivy Sacks are also an attractive option for backpacking hunters, backcountry skiers, and winter backpackers who want the lightest and smallest shelter they can carry for overnight or emergency use. Amazon. 25oz with the chest zipper option. - Size is 71"x108" (5. Learn to choose a bivy sack for ultralight backpacking trips and mountaineering. 9″ | Set-up Time: 1 min Aug 27, 2021 · Once thought of as the shelter for crazies, bivy sacks have steadily been gaining in popularity, especially in the ultralightweight backpacking community. Sep 18, 2019 · LytHarvest Ultralight Bivvy Bag Tent, Compact Single Person Backpacking Bivy Tent Military - 100% Waterproof Sleeping Bag Cover Bivvy Sack for Outdoor Survival, Bushcraft Portable & SAVE SPACE - Only 0. They can also be set up much faster than tents. I also had other nights in a tent, in alpine country, with condensation wetting out… Bivy Initial Setup Initial setup guide for your ANDA ultra light bivy. 4 days ago · Stay protected from the elements with the best bivy sacks of 2024. 6lb for entire kit, light wight and convenience to carry, easy to hold into your backpack. This Premium tent feature pre-sealed, seams and a durable reinforced rain-fly for enhanced waterproofness. Oct 7, 2019 · Emergency Sleeping Bag with Hood | Ultralight, Waterproof, Thermal Mylar Sleeping Bag Liner | Survival Bivy Space Blanket Bivey for Hiking, Backpacking, Earthquake, Camping, 72 Bug Out, Survival Kit Visit the Don't Die In The Woods Store 4. Ultralight Bivy (chest zipper): Our original bivy we've been selling since 2011. Best Emergency Survival Bivy Sacks. It's ultralight & compact, but not appealing to all. When we resume taking orders the lead time will be down to about ~4 weeks During the busy times of For winter I've used a cut down thermarest z Lite with my Alpha FL 45 rucksack extending the length plus, a DWR treated down bag and a mammut ultralight bivy sack or SOL. If without a tarp, then you really need a WPB bivy with a Goretex, eVent, or similar membrane. Sep 5, 2023 · This lightweight, fast-pitch bivy was designed in conjunction with mountaineers based on the criteria and livability they look for in the lightest, most convenient backcountry shelters. On Wir haben 55+ Biwaksäcke untersucht und die 11 Top-Modelle verglichen. When you need a really small footprint and you still want to be protected from the weather, a bivy sack is a great option. MLD Superlight bivy or Borah Ultralight bivy are two of the most popular. Aug 27, 2021 · Home - Sleeping Gear - Best Ultralight Bivy Sacks for a Daring Camper If you’re in a rush and want to find out what the best bivy sack is, we recommend the GEERTOP Ultralight Bivy Tent. A sudden change in the weather, an unforeseen event or an unplanned night in the mountains: A Bivi bag protects you Oct 3, 2019 · In the past, on some multi-day climbs, I slept under a tarp, with my quilt and air mattress inside a bivy sack. Featured review by Randy Why this bivy? I wanted to replace my three-season, two-man tent with something smaller and lighter, without sacrificing what I need to enjoy my trips. It's not right for every adventure, but here's where it shines. 87 Dan, the founder of ANDA, shares his journey of starting a cottage company and his participation in the REI Co-op Path Ahead Ventures x Founded Outdoors - Embark program. Other quilts and sleeping bags simply can't compare. Bivy sacks have the extra value of being much smaller than tents as well. Cuben Bivy: One of the lightest bivys we offer, weighing in at 4. Der BIVY ULTRALIGHT ist passend für ein bis zwei Personen und schützt vor den Elementen: Er ist winddicht und durch eine PU-Beschichtung außerdem wasser- und schmutzabweisend. 5 and 7. Extremely packable and lightweight. An in depth guide on choosing the best bivy sacks of 2024, with summaries of each and info on why they're essential for every adventurer. The Hyperlite Mountain Gear Splash Bivy, constructed with 100% waterproof Dyneema® Composite Fabrics and NoSeeUm Mesh, creates a modular, single-person sleep system that provides basic coverage on its own or in wet or buggy environments. Not sure what you need? Let us take you through the best options. Its durable Xtreme Shield coating effectively repels water for reliable protection A lightweight bivy sack with a full-mesh face panel and a unique zipper, the Borah Gear M90 Side-Zip Bivy is an ultralight essential weighing only 7 ounces. May 5, 2025 · A bivy sack is an excellent alternative to a tent. At just 12 ounces, it compresses small to not weigh down fast and light adventures. Perfect for solo camping or as a backup shelter on group trips, bivy tents keep you close to nature while shielding you from the elements. The Helium Bivy features Pertex® Shield Diamond Fuse 2. Gear reviews from our staff and members, buy/sell used, shopping tools, and more about the Borah Gear Ultralight Bivy. If you want ultralight minimalism, at the expense of strength, quality, and features, grab a plastic garbage sack and hit the trail. Our Burrito Bivy is your ground cover, wind stopper, splash guard, bug blocker solution. To test out bivy sacks we've huddled on mountain ledges and gone fast and light in the mountains. If you want rugged, solid performance in a bivy, this one is awesome. 13 – 0. 42LBS 1 Person Backpacking Tent for Camping Hiking Visit the MC Store 4. Enter the bivy sack – the minimalist’s answer to outdoor shelter. Compact and Lightweight - Bivvy tent is designed with convenience in mind. Whether you're camping, hiking, or simply enjoying the great outdoors, our bivy tent is a reliable companion for all your outdoor excursions. The proven draft-free, color-coded clip closures are nearly weightless and practically disappear when you're using the quilt on its own. Winterial Camping Tent, 1/3/6 Person Lightweight Personal Bivy 1 to 6 Person Tent with Waterproof Tent Rainfly, Durable Stitched Tent for Camping, Beach, Backpacking, Hiking, and Festivals. Jetzt mehr erfahren. The Bristlecone Bivy provides a waterproof floor with a water resistant upper to protect your quilt from spray and mist. Join us and ask yourself the question: Do I really need that? We would like to show you a description here but the site won’t allow us. 8 oz Dyneema ® Composite Fabric floor (floor color varies between gray and green, based on what DCF we have on hand) - Argon67 breathable/water resistant ripstop nylon top Jan 3, 2025 · Winter bivy sacks were first developed as solo shelters for mountaineering and climbing where participants were interested in lightweight and highly compressible camping gear. Get ready for fast-and-light missions with this clamshell-opening Outdoor Research Helium bivy. For the ultimate minimalist, the Trailhead Bivy is lightweight, packable, and breathable, made with hardwearing ripstop waterproof fabric. If you need help deciding between our Bryce and Zion tents, read our Paria Gear FAQ article that goes over the Jan 28, 2017 · Top Ranked Bivy Tent The Winterial Single Person Tent is perfect for 3 seasons of camping and hiking. 7 2,344 ratings 100+ bought in past month Jun 9, 2023 · Multi-functional - Rely on the high-quality materials of our single person tent, it can be used in different terrains and climates. All the ones you’ll find around that price point will have questionable breathability or weigh about as much as a roomier tent. Compact and lightweight, they're designed for adventurers who crave simplicity without sacrificing protection. We’ll cover some of our top picks below to help you find your next minimalistic shelter. Here's a step-by-step beginners guide to setting up an ultralight tarp and bivy. Move fast. Packed Size: 1’7" x 4" x 4" (48 x 12 x 12 cm). But this time with the high-tech, uber ultralight system handmade by Dan over at ANDA Ultralight. Der Ortovox findet sich jetzt unter „Außerdem getestet“. 0 21 ratings 100+ bought in past month May 26, 2023 · In my quest to find lighter and lighter ways to adventure into the mountains, I find myself back at my roots: a tarp and bivy setup. Our trekking pole tent excels with its meticulous GEERTOP Ultralight Bivy Tent for 1 Person 3 Season Waterproof Single Person Backpacking Tent for Camping Hiking Backpack Travel Outdoor Survival Gear Apr 21, 2025 · They should not be confused with much heavier waterproof bivy sacks used as tent replacements, such as the Outdoor Research Helium Bivy Sack. Feb 3, 2025 · As you’ll see, such ultralight bivy setups don’t take up much space or require awkward poles, and they allow you to fully enjoy sleeping under the stars. FREE shipping and Lifetime Warranty. Mar 11, 2025 · The ultralight bivy sacks that we use — the Katabatic Pinon and the Hyperlite Splash Bivy — offer a limited amount of standalone protection in the floor and lower side walls while maximizing breathability in the upper portion. Side Zipper Ultralight Bivy: This is the same as our Standard bivy with one exception. Super easy to set up but super easy to suffer from condensation issues. Ultralight, eco-friendly shelters to venture deeper into the outdoors. 3 oz silpoly floor. Gute Biwaksäcke sind leicht und wasserdicht. This three-season tents offer more open-air netting is specifically designed for summer backpacking and other activities. Designed to work well with both pyramid shelters and tarps. This bivy is for the serious ultralight backpacker who wants to save as much weight as possible. ORTOVOX Bivy bags BIVY ULTRALIGHT. They’re well worth considering if you’re heading out for an overnight hiking trip. 15D silnylon floor or 212g for M/Reg for 30D N66 floor. A waterproof bivy is a specialised piece of gear and mostly only good for use in the mountains, winter or if you expect to only get a few hours of sleep like during an endurance race. Made of a combination of nylon, TPU, and polyester, this helium bivy is waterproof, breathable, and easy to carry and use. Your Perfect Outdoor Companion: Onewind Ultralight Bivy Tent The Onewind Ultralight Bivy Tent is designed for solo adventurers seeking a lightweight, durable, and weatherproof solution for their outdoor escapades. Click now for more info! Dec 24, 2024 · Discover what a bivy bag is, its benefits for ultralight camping and backpacking, and how to choose the best shelter for your outdoor adventures. Feel light. These ultralight and weather-resistant shelters are perfect for extreme camping conditions and minimalist backpacking. 9oz How to Choose the Best Bivy Tent Weight and Size If you’re looking for the best bivy tent, then you’re looking for it to be small and lightweight. It's a very compact, feature-less bivy sack that embodies the essence of bivy sack camping. Aug 5, 2024 · Simple and lightweight, bivvy bags are a popular alternative to tents for a night of wild camping under the stars. 7x3. . 21 kg), they add approximately four to eight degrees of warmth, pack down next to nothing, and help to keep drafts at bay when you turn over in your quilt r/Ultralight is the largest online Ultralight Backcountry Backpacking community! This sub is about overnight backcountry backpacking, with a focus on moving efficiently, packing light, generally aiming at a sub 10 pound base weight, and following LNT principles. I'd recommend against this as they can be as heavy as an UL tent and will have a lot of condensation above freezing. And, the best bivy sack can easily compete with the most lightweight tent on the market. Size: 1-person | Season: 3-season | Tent Type: bivy, backpacking | Weight: 14 oz | Packed Size: 5″ x 5. Featuring a large mesh window and long U shaped zipper extending from waist level across the top, allowing for easy entry and exit. 9 lb for entire kit, aluminum poles, pack into a compact size 17 x 5 x 5 inch, easy to put the tent on backpack, good for 1 person backpacking travel,camping 【Waterproof Tent for 1 Person 】Up to PU5000 MM waterproof grade with the outer tent fly and the tent floor is PU8000 MM, fully seam taped and double 1-16 of 176 results for "ultralight bivy" Results Check each product page for other buying options. Standard Features: -0. We're currently not accepting new orders until July 28th, in order to work on sewing exisiting orders and reduce the lead times. The seams are deliberately placed high away from the ground in order to minimize any This ultralight emergency bivy sack offers the ideal amount of protection for wide range of situations without adding much to your pack—making it the perfect backup shelter. Bivy Sack recommendations? I'd like some recommendations for bivy sacks, but I'm mostly looking for smaller cottage industry makers which is why I'm asking you guys at ultralight. MSR says: The diminutive, ultralight and weather-resistant E-Bivy sa… The Zenbivy Ultralight Bed is the most comfortable and full-featured legitimately ultralight backpacking sleep system out there. Pair with a tarp in inclement weather. 7kg/1. Apr 11, 2025 · Aus den Empfehlungen herausgefallen sind dafür der Big Agnes Three Wire Hooped Bivy und der Ortovox Bivy Pro. May 1, 2024 · An ultralight bivy sack with big weather protection, the OR Helium Bivy is made from Pertex Diamond Fuse technology fabric. Oct 30, 2023 · The MSR Pro Bivy weighs less than 10 ounces. With soft featherlight fabrics, premium 900FP down, and patented comfort features that are inherently light, it turns out ultralight can be ultra-comfortable. Our lightest, most versatile backpacking sleeping bag systems. A thin membrane responds well to condensation, while providing high breathability. (Right side is also available for free, just contact us before ordering. Its lightweight, durable fabric with Diamond Fuse technology gives it its ultralight prowess. When packed in the included silnylon stuff sack, the bivy is barely larger than a water bottle. Most ultralight bivy sacks have mesh hoods for insect protection and comfort with a solid, highly breathable fabric, covering the torso and legs. Ultralight Bivi is a minimalist bivouac sheet, which is a good way to protect your sleeping bag against intense condensation inside the tent or snow hole. 3oz silpoly floor - waterproof and durable - Water Resistant/Breathable upper fabric in either Argon67 or Argon90 - 0. A sudden change in the weather, an unforeseen event or an unplanned night in the mountains: A Bivi bag protects you just when it really matters, and belongs in a mountain climber’s basic equipment. Ultralight Bivvy Bag Tent, Sleeping Bag Tent, Compact Single Person Backpacking Bivy Tent - 100 Waterproof Sleeping Bag Cover Bivvy Sack for Outdoor Survival, Bushcraft Nov 5, 2018 · For hikers that enjoy tarping and cowboy camping, ultralight bivy sacks represent an excellent supplementary option for your sleeping system. Set Apr 17, 2024 · MC TOMOUNT Bivy Tent Ultralight 2. Join us and ask yourself the question: Do I really need that? The Helium Bivy is an award-winning, ultralight, durable, minimalist shelter built with premium materials to move fast and light in all conditions. This video walks you through the contents you will receive with your ANDA bivy and how to set it up before you take it out on your first hike. com : Tact Bivvy® 2. In this article, we’ll go over different types of bivy sacks and some of the best models on the market today: Best Bivy Sacks. Price and other details may vary based on product size and color. Meant to repel splash, protect from drafts, provide full bug protection, add warmth to your system, and serve as a groundsheet. Perfect for a nice warm summer night with no fly and also great for Oct 11, 2022 · Convenient to Carry: The one person Bivy waterproof camping tent is light (only 1. Here are six of the best options for 2025 Apr 16, 2025 · Explore the best backpacking tarps for ultralight camping. com: ultralight bivy tentEach Carbonfree Certified product goes through a cradle-to-grave assessment to determine the product’s carbon footprint. If you’re on a solo trip or multi-day hike, lugging something bigger like a 4 person tent is a hassle. Top quality, great selection and expert advice you can trust. 6 pounds), easy to carry, easy to put into the backpack, and can also be well packed in a 15. Whether you need a free-standing tent, an ultralight tarp for your hammock, or a mesh tent / bivy for those stuffy summer nights, you'll find the perfect shelter for your needs. com Mar 23, 2025 · Ultralight bivy sacks are used by backpackers for cowboy camping or under floorless shelters, such as tarps or pyramids, to protect their sleeping bags/quilts and sleeping pads from wind, insects, mice, and other creepy crawlers. This great BIVY tent has features such as lightweight aluminum poles, durable stitching, full length flysheet, and taped seams for extra waterproofing. Weighing in at between 4. Package List: 1 x Tent Body 9 x Aluminum Tent Stakes 3 x Folding Aluminum Poles 1 x Windproof, Reflective Guy Rope 1 x Carry Bag for the entire package 4 days ago · Best bivvy bags for 2025 | Lightweight shelters for solo campers, tested by a backpacking expert Try a lighter, more adaptable approach to wild camping by ditching the tent and packing a bivvy. Best Value Bivy Tent: Eureka! SOLITAIRE AL. Contact us:Copyright © 2024, Borah Gear, All Rights Reserved Feb 16, 2023 · The Piñon Bivy is one of the most durable and versatile ultralight shelters I’ve used, and has been battle tested in the most horrendous of conditions over the course of the past year. 7oz no-see-um netting top - #3 YKK zipper across chest with two double sided pulls (if you want a side zipper, go here) - 5. Best Bivy Tents. Looking for a perfect ultralight bug shelter? When paired with a lightweight backpacking tarp, such as our Sanctuary Siltarp, our Breeze Mesh Bivy makes it one of the best values in ultralight shelters. If you Adds some extra warmth and wind protection to your sleeping system Cordlock at the end of the zipper allows you to lift the bivy away from your face 162g size M/Reg width. Everyone at Survival Frog is dedicated and passionate (borderline A Zenbivy Bed is designed like your bed at home, with a sheet below and a quilt above, offering unmatched comfort, freedom, and draft-free warmth outdoors. 5L technology, bluesign® approved materials, and intelligent design elements for lightweight, breathable, waterproof, and windproof protection while moving fast on trail and beyond. The carbon emissions associated with the product are reduced where possible, and remaining carbon emissions are offset with third-party verified carbon reduction projects in renewable energy, energy efficiency and forestry. Of course, there are some downsides—especially when it comes to dealing with bad weather—but for this trip, we had a pretty good idea of what to expect in terms of precipitation. Apr 10, 2025 · Headed outdoors and need a bivy sack? We've picked out five of the best bivy sacks on the market that are ideal for outdoor adventures! Jun 14, 2017 · Amazon. com : onewind Backpacking Tent for Single Person, 3 Season Ultralight Waterproof Silnylon Lightweight 1 Person Bushcraft Bivy Tent for Camping Backpacking Hiking, NO Trekking Pole : Sports & OutdoorsAbout this item Super Ventilation: Enhanced single-person tent with added rainfly for extra rain protection, keeping you dry in wet weather. Windproof and highly water resistant top fabric adds splash back protection. The ANDA Burrito Bivy is an ultra light backpacking bivy for those hikers wanting to do more with less on the trail and in the backcountry. All didn't go as planned. 100% Satisfaction Guarantee Best Bivy Sacks When it comes to lightweight backpacking and mountaineering, every ounce matters, and sometimes a traditional tent just isn’t the most practical option. The zipper goes across the chest just like on the Standard, but then takes a turn down the left side for 24", creating a bivy that is easier to get into. Jan 16, 2024 · The Borah Gear Ultralight Bivy is a well-made lightweight bivy and I purchased for a solo trip. Compact yet spacious, this 1 person bivy tent offers ultimate comfort and protection for backpackers, trekkers, and campers alike. Die Silberbeschichtung auf der Innenseite, welche die Körperwärme reflektiert, hält Kälte draußen. The reason why outdoor enthusiasts opt for a bivy tent is that they offer a lightweight and portable alternative to a traditional tent. The Pro Level SuperLight Solo Bivy ™ was the first DWR (Durable Water Repellant) top entry, super-light backpacker bivy with a net face window! May 15, 2020 · The Borah Gear Cuben bivy is an ultralight, ultra-packable, water resistant bivy with bug netting top. Discover options to reduce gear weight while enhancing outdoor experience. May 9, 2024 · Bivy sacks are the original ultralight shelter. Dec 5, 2023 · Best Bivy Sacks Reviewed Bivy sacks fill a specific niche in the hiking and camping world. 100% Satisfaction Guarantee Shop for Bivy Sacks at REI - Browse our extensive selection of trusted outdoor brands and high-quality recreation gear. Silpoly Solo Tarp: These are our solo tarps made from lightweight 100% waterproof silpoly fabric. A waterproof bottom fabric keeps you and your sleep system dry. Borah Gear: Ultralight Bug Bivy r/Ultralight is the largest online Ultralight Backcountry Backpacking community! This sub is about overnight backcountry backpacking, with a focus on moving efficiently, packing light, generally aiming at a sub 10 pound base weight, and following LNT principles. We offer versatile, lightweight, and affordable backpacking shelters for your next backpacking trip. It is made of waterproof, ultra-light Pertex® Quantum Pro fabric. r/Ultralight is the largest online Ultralight Backcountry Backpacking community! This sub is about overnight backcountry backpacking, with a focus on moving efficiently, packing light, generally aiming at a sub 10 pound base weight, and following LNT principles. 5 oz (0. Nov 20, 2016 · A tarp & bivy system excels in the West, where dry & bug-free nights are the norm. 5 oz | 180 gm Another MLD Original – the first top entry Ultralight Bug Net Bivy! Bug Protection + Great Ventilation for Medium to Warm Climates. Jan 28, 2019 · Product Description The MSR E-Bivy Ultralight, Water-Resistant Emergency Shelter with Stuff Sack is an ultralight bivy sack that’s weather-resistant and supremely packable making it the perfect emergency shelter for any adventure, emergency preparedness kit or bug-out bag. 0 HeatEcho® Emergency Sleeping Bag, Compact Ultra Lightweight, Waterproof, Thermal Bivy Cover, Emergency Shelter Survival Kit – w/Stuff Sack, Carabiner, Survival Whistle + ParaTinder : Sports & OutdoorsLocated in Denver, Colorado Survival Frog is a small business living in the big world of Amazon. Stay present. MLD BUG BIVY Bug Freedom WEIGHT: 6. Mar 5, 2023 · The Borah Gear Bug Bivy is an ultralight bivy constructed with . 9'x9') - Xenon 20d ripstop silpoly is low stretch and doesn't sag in the rain - Flat tarps provide nearly unlimited different set-up options - Ties outs at each corner and at mid-points, 8 total - Bivy mitten hooks at ridge ends - Silpoly stuff sack included - Weight: 7. This bivy keeps users dry and warm when paired with a good sleeping bag and sleeping pad. Podcast: Ripstop on the Record, Ep. Left side is by default) All fabric types/sizes are the same as our Standard, only Aug 29, 2012 · July 2025 - Lead times update, pause on new orders (updated July 9th) Current lead time for new orders of bivys and tarps is now 8 weeks from order date to ship date. They’re small, lightweight, and easy to setup and breakdown. Nov 6, 2024 · Amazon. Mar 23, 2016 · LIGHTWEIGHT & BREATHABLE: Be prepared for a night of adventure by carrying this lightweight sleeping bag. 9 ounces for standard length, standard girth in About this item Aluminum Imported 【Ultralight Backpacking Tent】Weigh about 2. rjcy dayu qlvlm bjlhnod nfykyke jczr zhhq ucapdl rgxt bzufd