A brick and frozen water have a couple of things in common. They’re both hard and aren’t worth a lick when you’re thirsty on a ski tour. And what could beat a slow, cold pull from your reservoir in the baking heat of summer? That’s why we made this insulated reservoir sleeve. Including a deluxe Big Zip SL reservoir and our Bite Valve and Drink Tube Insulator, you’ll be assured your water is just the way you like it, all year long. A rugged Cordura exterior protects your reservoir and seals up tight with a side-release buckled lid.