The Roadster I utilises two Velcro straps to secure the bag onto the saddle rail and seat post. It features a loop to attach a rear light. Its narrow 4cm wide body reduces the chances of your thigh rubbing against the side of the bag during rides. The bag is made of 300D Water-Repellent Polyester that keeps the content dry in muddy or wet conditions. Storage capacity of 0.3L is sufficient to carry a 700c tube, a pair of tire levers and a CO2 cartridge Bag size: 13 x 7 x 4cm