Since the first iteration of the Zygos, tens of thousands of runners have utilized this high-capacity 14 liter race vest. The lightweight and comfortable wrap-around design complimented by the ErgoFit Harness ensures the Zygos 6.0 will be stable, comfortable, and hindrance free. The pack&&';;s MaxO2 Form adjustable closure system secures and adapts to the pack&&';;s load. This innovative system can conform the pack to the body using a single pull. Similar to the MaxO2 Sternum, this system allows the pack to remain secured without impeding natural breathing. Featuring 12 pockets total, 10 of them being accessible on-the-go, the Zygos 6.0 prioritizes access and gear allocation. The main back compartment has been reinforced at the stress points with XT fabric which contains stronger than steel ripstop fibers. This pack includes 2 800 mL Softflasks and is compatible with a 2L Reservoir and any of our other hydration options. Details Silicone and PU coated feather-weight nylon fabrics resist water, abrasion and tears. Max O2 Form(TM) 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. 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 Size(s): Small (30"-35") Medium (35"-40") Large (40"-45") Hydration (included): 2x 800 mL SoftFlasks Hydration Compatible (not included): 2L Reservoir, 500mL softflask, 550 UltraFlask Capacity: 854 c.i. (14L)