When you need extra storage on the bike you take it where you can get it thats why we designed our top tube pack to be a small out of the way solution for carrying your smaller ride essentials and gear it features a nylon coated mesh construction thats weather resistant in order to keep the bags contents safe and dry which is further amplified by the weather resistant ykk zipper at the exterior and to make it easy to get on and off the bike it has a simple to use three point velcro a