Just load the necessary items with the included straps and attach them to the rails on the saddle, seatpost or down tube with the hook and loop strap. The included 2 removable nylon straps allow for quick removal and access to attached gear for emergencies and repairs on the trail. MATERIAL Polyester hook and loop fastening strap with built-in bungee strap / 2 detachable Nylon straps ATTACHMENT Hook and loop fastening strap with anti-slip and scratch-free fabric MOUNT Saddle rails, seatpost or downtube SIZE 72 x 3.8 cm / 28" x 1.5" (L) 69 x 2.5 cm / 27" x 1" (M) 50 x 2.5 cm / 20" x 1" (S) WEIGHT 47 g / 1.66 oz (L) 33 g / 1.16 oz (M) 28 g / 0.99 oz (S)