Expandable UltraMax fabric back bag for maximum UV protection. Mounts on luggage rack, sissy bar or seat with quick-release straps. It can contain 2 full face helmets even when not foamed. Features: - Rigid construction: a rigid base panel prevents collapse - Fully lined interior with rigid structure - Supports for most travel trunks, including: Harley Ultra, Goldwing, Indian Roadmaster, etc.. - Feasibly expandable up to 3" - quick access front pocket with zip closures - 3 spacious outside pockets - reflective bands to improve visibility - 3 carrying handles - waterproof rain cover included Main compartment dimensions: 55.9 x 30.5 x 36.9 cm (63 litres) Top compartment dimensions: 55.9 x 30.5 x 43.2 cm (73.5 litres)