Zygos 2.0 Hydration Pack

Rated 5.00 out of 5 based on 6 customer ratings
(6 customer reviews)


The Zygos 2.0 hydration pack is very versatile and Bryce Thatcher’s pack of choice. This pack is lightweight and high capacity, a comfortable wrap around style with full compression allow for the lowest profile empty or fully loaded. The Zygos 2.0 comes with a 2L reservoir and a magnetic clip to keep your hands free. Whether you are fast-packing, mountain biking, in a fast race, ultra race, or a summit assault this hydration backpack is the solution for any athlete. Available in three sizes for a more comfortable 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 (30″-34″), Medium (33″-37″) or Large (36″-42″)
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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6 reviews for Zygos 2.0 Hydration Pack

  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

  3. Rated 5 out of 5

    Chris Talley

    I love my Zygos! It is light and yet carries so much gear. The shock cords make it highly adjustable so it always fits comfortably.

  4. Rated 5 out of 5

    Bruce Grant

    My Zygos 2.0 has proven to be the most comfortable pack I have worn over many years. It fits me very well (size M for a 5’7″/155lb body) , with the load comfortably distributed over the broad harness. Pockets are all within easy reach, compared to the uncomfortable contortions needed for some other packs. Fabrics used in the straps and pockets are breathable, so those areas don’t get too hot and sweaty depending on what is crammed into them. Carrying capacity is quite high, so there is plenty of room for food, clothing and safety gear for 100-milers or long backcountry endeavours, though the pack weight is light enough to use it for shorter distances as well. Bottles are mounted at an optimal position on the lower chest so they don’t bounce or shift, while also leaving room on the shoulder straps for decent-sized pockets that are easy to access. Finally, the pole-mount straps at the back are handy and easy to use without removing the pack.

  5. Rated 5 out of 5

    Richelle Criswell

    I have been running with UltrAspire for the past 5 years. In preparation for a 40 mile trail race with only 2 aid stations, I decided to go with a hydration pack that allows me to carry plenty of water (bladder and two 250mL collapsible bottles) as well as additional nutrition and gear. The Zygos has been the perfect choice. After speaking with customer support (who are always friendly and helpful), I was able to select the correct size and then placed the order. I’ve used it for multiple training runs and have been please with the many options because of all the various pockets (sizes and placement) on the pack. This pack is a great addition to the Astral, Spry, and handheld so that I have the correct hydration gear no matter what distance and terrain.

  6. Rated 5 out of 5


    I have used the Zygos 2.0 for about 9 months. It is a great pack with enough carrying capacity for a full day. Some of the features I really like are the magnetic clip for the hose. I did have to zip tie the part that stays on the pack to keep it from sliding off. The new tab for holding the bladder in place works great and is easy to detach for quick refills. Recently, I carried five liters of fluid (2 liter bladder, two 1/2 liter soft bottles up front, and four bottles 1/2 liter bottles in the pack) for about 6 miles. This was for an all day run with no water refills and I cached 2 liters at mile 6. I was surprised by how well the pack carried when loaded with over 10 lbs. and felt like I would have been ok carrying this much weight all day if I had to. The side pockets are super convenient and hold a lot of food or you can put a cell phone in one side. The elastic front closures are a great feature allowing one to quickly loosen or tighten the pack fit. The pack rides well overall and seems to be very durable with no signs of wear after nine months of heavy use and a few times through the washing machine.

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