The Latest product from Stebles Bikes, is the future of saddle bags, this 3D printed design has been made specifically to fit the essentials you need a Schwalbe SV20 superlight 700c inner tube, 2 Park Tools Tyre levers and Park Tools Super Patches incase you have more than one puncture on a ride. The Aero Box comes complete with the tube, patches and levers, and 4 x 8mm wide strong cable ties to attach it to the bike. All the internal are deisgned to be a tight fit so nothing will rattle around. It can be fitted on the seat post itself of if you have a large frame, then on the seat tube of the frame facing the wheel or for smaller frames facing forward. Designed to fit a standard 34.9mm diameter seat tube of the frame, which is what most frames have these days if the seat post is 30.9 or 31.6. It will also fit well on smaller diameter seat tubes and post fine. It is 3D printed to order in many different colours, please ask. As Reviewed by Road.cc website