Pioneering the Future of Ultralight Insulation

Zenbivy was the first to introduce Muscovy to the outdoor market—now, we’ve expanded that innovation even further, pioneering ExpeDRY™ Muscovy and Ultrasonic Muscovy™ 950FP, and introducing our first-ever synthetic Ultralight Bed powered by PrimaLoft® Gold insulation.

Next year, you’ll be able to choose from four colors and four premium insulations—including the tried-and-true ExpeDRY™ Goose 900FP—redefining what ultralight comfort and performance mean in the backcountry.

Arriving Fall 2025

ExpeDRY™ Muscovy 900FP

Zenbivy is proud to be the first to bring ExpeDRY™ Muscovy to the outdoor market. By combining the next generation of water-resistant down technology with the lofty resilience of Muscovy down, we’re setting a new benchmark in warmth, performance, and sustainability.

Built For:

Long distance thru-hikers, or ultralight backpackers who frequently find themselves in humid climates.

Benefits of ExpeDRY™

  • Chemical-Free

    ExpeDRY™ is chemical-free, bonding non-toxic gold particles to each down cluster to aid in evaporation and keep insulation dry without harsh chemical coatings.

  • Dries Faster

    Testing shows ExpeDRY™ dries up to 50% faster than chemically treated down. In real-world conditions, humidity—not liquid water—causes down to get wet. ExpeDRY™ is the first “active insulation” that accelerates evaporation instead of simply repelling water.

  • Permanent

    Unlike chemical coatings that wash out or wear off over time, ExpeDRY’s gold particle treatment bonds permanently to the down cluster.

  • Sustainable by Design

    ExpeDRY™ uses reclaimed gold and requires up to 70% fewer resources in production—delivering high performance with a lower environmental footprint.

Benefits of Muscovy

  • High Loft

    Muscovy effortlessly achieves 900+ fill power, the highest of any duck down.

  • Superior Stability

    Muscovy down has an inherent "clinginess", which creates more stability and reduces shifting.

  • Fast Compression Recovery

    Exceptionally resilient and strong, Muscovy down "springs back" at a faster re-loft rate than other downs.

  • Affordable Excellence

    Premium warmth and performance at a lower cost than goose means you can get the best, for less.

Zenbivy Half Length sheet in gray, lightweight and packable camping sheet designed for ultralight backpacking sleep systems.

New! ExpeDRY™ Muscovy Ultralight Sheet

Complete your ExpeDRY™ Muscovy Ultralight Bed with a matching sheet that carries the same breakthrough performance through every layer of your sleep system.

White abstract down plume with smaller bubbles surrounding it on a black background

Launching early 2026

Ultrasonic Muscovy™ 950FP+

The highest lofting Muscovy down ever! At an unmatched fill power, Ultrasonic Muscovy™ 950FP+ delivers maximum warmth at the lowest weight—pushing the limits of what’s possible with natural down.

These are our lightest Ultralight Beds yet.

  • Save 0.5 oz on the 25°F
  • Save 2+ oz on the 10°F

Built For:

Serious ultralight backpackers who demand the absolute lightest, highest-performing natural down insulation available.

Benefits of Ultrasonic Muscovy™

  • Additive-Free, Achieving Highest Fill Power

    Unlike treated downs, untreated down clusters preserve their full loft. This results in the highest lofting Muscovy down ever—providing maximum warmth at minimum weight.

  • Cleaner than Other Duck Downs

    Ultrasonic Muscovy™ undergoes a unique, patented Ultrasonic Washing process and far exceeds the industry standard for cleanliness, resulting in an ultra-clean and virtually odor-free down.

  • Uses Less Water & Energy

    Because the patented Ultrasonic Washing Technology cleans down more effectively, the process uses 20% less water and energy through fewer rinse cycles, resulting in a high performance down that is not only cleaner, but more environmentally friendly as well.

Launching early 2026

PrimaLoft® Gold

Introducing our first-ever synthetic Ultralight Bed! The industry leader in synthetic performance and technology, premium PrimaLoft® Gold insulation is thoughtfully engineered from ultra-fine fibers, delivering lightweight, thermally-efficient performance.

Person unpacking their Zenbivy Pack Liner in a yellow tent in a rocky area with a glacier in the background.

Built For:

Ultralight backpackers who can't use down (allergies or sensitivities), or don't want to use down (personal or ethical preferences).

Performance

  • Exceptional Warmth-to-Weight

    Compared to other synthetics, PrimaLoft® Gold achieves the same level of warmth for less weight.

  • Packable

    Compresses easily to save space in your pack.

  • Ultra-Soft

    Extra fine fibers create a down-like, ultra-soft feel.

  • Durable

    Designed to withstand years of adventure and repeated washing.

Sustainability

  • Recycled Materials

    Made with up to 100% recycled materials, sourced primarily from plastic water bottles.

  • Reduced Emissions

    PrimaLoft’s Unique manufacturing process cuts carbon emissions by more than 50%.

  • Landfill & Ocean Impact

    PrimaLoft has diverted nearly 1 billion plastic bottles from landfills and marine environments over the last decade.

  • Enabling Circularity

    Built with recyclability in mind for a sustainable end-of-life solution.

New! Synthetic Ultralight Sheet

The final piece to complete your synthetic Ultralight Bed. For the first time, those who prefer synthetic can enjoy the same full "mummy-bag warmth" as down users. The Ultralight Sheet Synthetic features an insulated hood rated to 25°F.

Ultralight Bed Specifications

Limit/Comfort

25°F Down: 25°F (-4°C) / 35°F (2°C)

10°F Down: 10°F (-12°C) / 20°F (-7°C)

Fabrics

Liner: 10D Pertex® Quantum, coating-free, cire, fluorocarbon-free DWR (PFAS-free)

Shell: 10D Pertex® Quantum, coating-free, cire, fluorocarbon-free DWR (PFAS-free)

Wing panels on Ultralight Sheets: 15D Nylon Taffeta, coating-free, cire, CO DWR (PFAS-free)

Sheet Sizing

20": Fits mattresses up to 21" x any length x 4" thick (or 3.5" if 3D)

25": Fits mattresses up to 26" x any length x 4" thick (or 3.5" if 3D)

Recommended Dry Sack Size

Down Ultralight Beds

  • 25°F: 4L - 7L
  • 10°F: 10L

Synthetic Ultralight Beds

  • 25°F: 10L

Includes

Ultralight Quilts include quilt and mesh storage sack. Ultralight Sheets includes sheet only.

Quilt and sheet sold a la carte. Ultralight Quilts are compatible with any size Ultralight Sheet. Mattress and accessories sold separately.

By Fill

ExpeDRY™ Muscovy 900FP

Fill & Fill Weight

Fill: 900FP ExpeDRY™ water-resistant 90/10 Muscovy down (PFAS-free)

Ultralight Quilt 25°

  • Regular: 286g
  • Large: 326g
  • XL: 376g

Ultralight Quilt 10°

  • Regular: 513g
  • Large: 598g
  • XL: 693g

Ultralight Sheet 25°

  • 20": 44.5g
  • 25": 46.5g

Ultralight Sheet 10°

  • 20": 79g
  • 25": 84g

Product Weight

Ultralight Quilt 25°

  • Regular: 1 lb 1 oz | 482g
  • Large: 1 lb 3 oz | 538g
  • XL: 1 lb 6 oz | 623g

Ultralight Quilt 10°

  • Regular: 1 lb 10 oz | 737g
  • Large: 1 lb 14 oz | 850g
  • XL: 2 lb 2 oz | 963g

Ultralight Sheet 25°

  • 20": 5 oz | 141g
  • 25": 6 oz | 170g

Ultralight Sheet 10°

  • 20": 6 oz | 170g
  • 25": 7 oz | 198g

MSRP

Ultralight Quilt 25°

  • Regular: $359
  • Large: $389
  • XL: $439

Ultralight Quilt 10°

  • Regular: $469
  • Large: $519
  • XL: $589

Ultralight Sheet 25°

  • 20": $139
  • 25": $139

Ultralight Sheet 10°

  • 20": $159
  • 25": $159

Ultrasonic Muscovy™ 950FP+

Fill & Fill Weight

Fill: 950FP+ Ultrasonic Muscovy Down™ 90/10 grey duck down (untreated)

Ultralight Quilt 25°

  • Regular: 271g
  • Large: 309g
  • XL: 356g

Ultralight Quilt 10°

  • Regular: 461g
  • Large: 525g
  • XL: 605g

Ultralight Sheets not available in Ultrasonic Muscovy™ 950FP+

Product Weight

Ultralight Quilt 25°

  • Regular: 1 lb 0.5 oz | 468g
  • Large: 1 lb 2.5 oz | 524g
  • XL: 1 lb 5.5 oz | 610g

Ultralight Quilt 10°

  • Regular: 1 lb 8 oz | 669g
  • Large: 1 lb 11 oz | 760g
  • XL: 1 lb 15 oz | 868g

Ultralight Sheets not available in Ultrasonic Muscovy™ 950FP+

MSRP

Ultralight Quilt 25°

  • Regular: $379
  • Large: $409
  • XL: $459

Ultralight Quilt 10°

  • Regular: $489
  • Large: $539
  • XL: $609

PrimaLoft® Gold Synthetic

Fill

Fill: Primaloft Gold 1-1001 synthetic insulation (100gsm x 2 layers)

Product Weight

Ultralight Quilt 25°

  • Regular: 1 lb 8 oz | 703g
  • Large: 1 lb 12 oz | 784g
  • XL: 2 lb 1 oz | 938g

Ultralight Sheet 25°

  • 20": 8 oz | 226g
  • 25": 8.5 oz | 243g

Ultralight Bed Synthetic is only available in 25°F.

MSRP

Ultralight Quilt 25°

  • Regular: $329
  • Large: $359
  • XL: $409

Ultralight Sheet 25°

  • 20": $139
  • 25": $139

Specifications and MSRP are subject to change upon official release.

Ultralight Zenbivy sleeping bag system with gray and white quilt, displayed at high-altitude campsite by glacial lake and rocky cliffs.

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