When we need to guarantee that our clothes, sleeping bag, and electronics stay dry, we stuff them in Aero's Heavy Duty Dry Bag. The thermoplastic polyurethane construction provides durable waterproofing with convenient loopholes that let us attach the bag to a range of racks, cages, and handlebar or fork cradles. The 12L capacity is a versatile size for bike packing--with enough room for essentials without being too bulky.