Zygos 2.0

Rated 5.00 out of 5 based on 2 customer ratings
(2 customer reviews)


Light and sleek aerodynamic efficiency one with air and earth. Instinctual, intuitive, primordial—a tour de force. You are the Zygos.  Lightweight, high capacity, wrap around style with full compression for lowest profile empty or fully loaded. For a fast race, ultra, summit assault, overnight “fast-packing” and even mountain biking. Now carry Z poles, and access bottom zippered pocket on the go.

Bryce Thatcher’s pack of choice. Available in three sizes for a more comfortable and solid feel and fit.



Recommended Use:
50k to 100 mile Ultra trail racing in high mountains or with required gear lists


• Lightweight, soft, breathable, but strong, large-holed mesh pulls moisture away from the body to keep skin dry and cool.
• Silicone and PU coated feather-weight nylon fabrics resist water, abrasion and tears.
• Max O2 Sternum™ for unrestricted breathing while maintaining a stable pack. Uses shock cord with good stretch for unrestricted breathing but also good rebound on the stretch for a stable ride. Patent Pending.
• Plush feeling micro-fiber polyester edges, soft and non-abrasive against skin and clothing.
• Sweat proof webbing—won’t absorb water or get saturated and heavy.
• Safety stitched bar tack on all stress points.
• Quiet, bounce free, easy to see and use, zipper pulls.
• Zig zagged stitching over elastic for ultra-durability, increased stretch and rebound.
• Simple, fast, easy in and out bladder attachment.
• Magnon pocket for sweat-free pills, with automatic magnetic closure for rapid access to pills and other essentials. Patent pending.

Fit:  Unisex
Size(s):  Small, Medium or Large
Color:  Luminous Blue/Precipitous Blue
Hydration (included):  2L Reservoir with mag-clip to secure hose.
Bottle Compatible (not included):  UltraFlask, Formula 250, Human 20 oz 2.0, or Collapsible Bottle
Capacity: 570 c.i. (9.34 L)

Additional information

Weight N/A
Dimensions N/A


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Fluid Capacity

2 L (70 fl. oz) Reservoir

Total Volume

9.34 L

Product Dimension (inches) LxWxH

Weight (Includes Reservoir)

14.0 oz (396 g)


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2 reviews for Zygos 2.0

  1. Rated 5 out of 5

    Stephane Guimond (verified owner)

    My “Go” to everything bag!

  2. Rated 5 out of 5

    James Lavin

    I can’t imagine a better race bag. Just used it for Transelkirks and it was far superior to my other packs. One, its very comfortable–the elastic chest straps really work to keep it in place under any conditions and are remarkably confortable. One note of caution, the large is large for trail people–not normal people and don’t think it will work for anyone above 190. The front pockets held the mandatory bear spray and an Ultraspire soft flask without ever chafing or obstructing. The best feature was the underpack loops for tri-fold poles. I pulled them on and put them back in dozens of times without breaking stride. Perfect. And the small pocket under the bag was great for my unfortunately needed blister kit. Pockets everywhere for both phone gps and lots of GU’ss and bars and the waste. And held rain pants, hat, gloves and rain jacket easily in main pack. Hydration also very easy access. Fabulous pack

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