new and made of special metal material to a long lifespan, very sturdy. Helpful when increasing power out of a slower corner, or when powering up a steep climb. Changes the degree of rear hub engagement, dramatically increasing the hub's engagement response. For DT 18T Replacement accessories Colour:Silver Material:alloy steel Type: 54T Package Contents: 1x bike hub ratchet Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.