BPA-FREE HYDRATION ON-THE-GO: No matter how you travel, backpack hydration is ideal for ensuring you don't get dehydrated when you're busy. Hydration Bladders are made with BPA-free, FDA-approved plastic rated for temperatures between -5 and 120 degreesFahrenheit, and feature pressure tolerant, double-sealed, thermally welded edges. A MUST-HAVE FOR OUTDOOR ADVENTURE: These bladders are perfect for travelers, commuters, motorcyclists, endurance sports lovers, and outdoor enthusiasts like hikers, runners, cyclists, snowboarders, campers and rock climbers. Compatible with most hydrationpacks, simply fill with fresh water and insert into a backpack. To hydrate, gently bite the valve and sip as you would from a straw. 4" WIDE-MOUTH for EASY ACCESS: These bladders feature one of the largest screw cap openings of any hydration bladder available, making it easy to fill with liquid, add ice on hot days, or thoroughly clean the interior by hand or with a bottle brush. SILICONE MOUTHPIECE with LID: Get more water with every sip from a high-flow bite valve, made with smooth, medical-grade silicone and an integrated dust cap to ensure easy drinking and keep the mouthpiece clean. You control the water flow with pressure. DURABLE QUICK RELEASE TUBE: Unlike some designs, our tube has an on/off valve that locks in place so the tube wont come loose in your pack, causing water to leak out. Whenever you need to remove the tube for cleaning, travel or storage, simply closethe valve to automatically seal the bag and prevent fluid loss. Meet your new adventure buddy! Hydration Bladders are made to help people living an active lifestyle stay hydrated on-the-go. Drinking water from a water bottle can be problematic for a number of reasons. If you're running or hiking, you have tocarry a bottle with you. If you're mountain biking, road cycling, riding a motorcycle, or rock climbing, you don't exactly have free hands, now do you? It's because of these limitations that we often forgo drinking water throughout the day, as we should. And by the time we feel thirsty, dehydration has already set in.