Seat-Pack QRWhether youre riding singletrack, mountain passes or gravel routes, with the waterproof Seat Pack QR you are ready for every bike adventure. With the innovative and patented Seat Lock attachment system and abrasion resistant nylon fabric, the bag is super stable, quickly mounted and just as quickly removed without leaving any residue. And with the help of a special adapter of just 4. 3 centimetre in width, this bag can even be used with a dropper