Most riders use a hydration pack for the ease and convenience of drinking while riding. Safer, faster, easier, with more capacity than water bottles, a hydration pack is the key to rides over an hour on the trail. Of course trails feature dirt, detritus, mud, and though not often seen, animal droppings. The Osprey Hydraulics Bite Valve Cover may be an impediment to fast access, but it can surely prevent dirt and mud from contaminating the Bite Valve. This is a good thing, as most people don't enjoy dirt or mud, and fewer enjoy giardia or some other gut wrenching parasite or bacteria. And yes, it is not only possible, but it happens more often than you'd think. So get this Bite Valve Cover that is designed to perfectly integrate with your Osprey Hydraulics system, and take the kind of risks on the trail that involve gaps, rocks, and hops.