The DeFender M1 is compatible with all front forks including tapered steerers. The unique quick release attachment system integrates seamlessly.The 2 pivot arm of the M2 articulates for improved coverage and a perfect bike fit. A stiff engineering grade plastic support frame is co-moulded to a more flexible edge for greater durability.Quick release for front and rear,Fits 25.4mm to 34.9mm seatpost,230g (Front), 190g (Rear).