ThermoBak 3L is a low-profile solution that offers the versatility to be worn as a standard hydration pack or attached to the back of the IOTV/MTV with our Direct Armor Attachment System (D.A.A.S.). Updated with durable 500D double-rip Cordura fabric and the new 3L (100oz) Mil Spec Crux Reservoir, the ThermoBak 3L maintains it’s minimalist footprint while offering 25% more water per sip.