Features: 20mm Pretension Bolts designs specifically for cranksets. Make of aluminum alloy, rustproof, strong, firmly and Enduring. Ensures secure fixation of the crank for chainsets. This product is used to fix the crank and crank of the sprocket. It is a great accessory for bicycles enthusiasts. Specifications: Materials: Aluminum alloy Color: Gold or Pink or Black Cover diameter: about 26mm or 1.02inch Thread diameter: about 20mm or 0.79inch Package Includes: 1pc Crankset Cover note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color. 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.