Listen to the Geigerrig Cadence review.  This hydration pack comes with the VERY cool pressurized hydration bladder that eliminates any sucking.

Bladder: 50 oz., quick-release valves for drinking tube and pressurization tube for easy refill and bladder removal, slide top for easy refill, cleaning and drying.

Fabric: Poly Mesh – Stretch, Breathable, Light Weight

Length: 15.5"

Width: 13"

Weight: 1.15 lbs

List Price: $145

comes with optional inline filter