The best selling hydration system from Source Tactical, the 3-liter Tactical hydration pack offers a variety of usage modes -- worn backpack style, inserted in rucks, or direct-attached to MOLLE on vests or rucks using the Source QCA buckle system. The Tactical features quick-release shoulder straps that can be folded into a back pocket to load into a larger pack or mount on gear. A zippered top opening provides quick and easy access to the reservoir for cleaning, draining, or replacement. Closed cell insulation keeps the liquid cool for better absorption by the body. Other features include an external fill port, sternum strap for added stability, and elastic secured loop to keep loose strap-ends from dangling. The Tactical comes with a 3-liter WXP reservoir (BPA and phthalate free), which features a wide opening for easy filling, cleaning, draining, and ice insertion. Source's Glass-Like Film prevents bio-film build up and making the system virtually self-cleaning. Grunge Guard Technology inhibits bacteria growth on the reservoir and drinking tube surfaces for the life of the system. The WXP is complemented by the high-flow Storm valve, a push-pull system that's like drinking from a straw. Source has been a ground breaker in hydration system technology and is also well known for its tactical gear and hiking sandals. Tested in the most extreme conditions, hundreds of thousands of Source hydration systems are in use in the field.