DESCRIPTION STABLE WATERPROOF BACKPACK SHELL This motorcycle backpack uses a 500D PVC mesh exterior, 600D waterproof Oxford fabric, and a silver-gray voltage-laminated lining, making it a tear-resistant, abrasion-resistant dry bag backpack that holds its shape on every ride. 21L CLOSED, 30L EXPANDABLE This roll top dry bag shifts from compact 21L closed storage to 30L open capacity, so one waterproof backpack carries your gear, clothes, and essentials for day rides, commuting, and travel. IPX5 WATERPROOF DRY BAG A roll-top closure with internal voltage-laminated waterproof construction gives this waterproof dry bag IPX5 splash protection, helping keep your phone, wallet, and spare clothes dry in heavy rain, road spray, and shallow water. STABLE STAY-PUT FIT Adjustable sternum and widened waist straps keep this motorcycle backpack close to your body, cutting side-to-side swing and up-and-down slip on bumpy roads, high-speed runs, and unpaved routes. HIDDEN HELMET NET & REFLECTIVE TRIM A zippered helmet net tucks under the base and unfolds in seconds for hands-free helmet carry after parking; reflective geometric panels add nighttime visibility for late rides.Great as a waterproof dry bag for kayaking, boating, paddle boarding, fishing, camping, and hiking; a waterproof travel backpack for vacation and commuting; and a waterproof beach bag for beach days and cruise ship essentials. FITMENT Universal Fit