Universal mount system offers endless mounting options. Heavy duty 1200 denier fabric. Each end compartment expands by 1.5 inches for extra storage. 3 compartments feature waterproof zippered ends and large main hatch for easy accessability. Semi-rigid design that will maintain its shape empty or full. Measures 8 inches in diameter and 19 inches long - expanding to 23 inches. Bag comes complete with mounting and shoulder straps and rain cover.