Packing: 2PCS. Material: plastic + metal screws. Size: 40x28mm/1.57x1.1inch. Robust, highly durable and environmentally safe with a long service life. Mounts on the frame below the bottom bracket to provide a low friction surface for the gear cable. If a drop-down front derailleur is used, it is an important part that guides the brake and shift cables between the front and rear shifting/braking systems.