600d nylon/420d ripstop fabric hydration pack. The 30 miler includes a 2 liter peva hydration bladder and tube with bite valve. Features a large main compartment with double hooked bladder pocket and space for other gear; a front compartment with interior organization; a small front zipper pocket; 2 side mesh pockets; adjustable shoulder straps and sternum strap; padded back with air channels; and reflective tape detailing. Keep yourself hydrated during any excursion!