The ortlieb rack pack travel bag x large is an 100 per cent waterproof bag with all the benefits of an easy to use dry bag youll find its flexible and variable packing volume easy to adjust to any situation whether you are travelling or packing your sports gear the roll closure with stiffener bar comes from stuff sack technology the rack pack fits perfectly onto bike trailers using buckles the rack pack travel bag is comfortable to carry thanks to the adjustable padded shoulder strap and