Features: Make of aluminum Alloys, light weight, strong and enduring. Equipped with 18/20mm rubber rings, suitable for most hollows cranksets. The crank cover can protect the crank from scratches and dust. Good sealing, water resistant, this bike crank cover can protect the crank. Suitable for mountain bikes, road bikes. Specifications: Materials: Aluminum Alloys Color: Black/Red/Blue color/Gold/Silver/Purpleness Size: about 25.8x8.6mm/1.02x0.34inch Package Includes: 1Pc Bicycles Teeth Plate Crank 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.