Description: Designed with high hardness, this chainring bolt is anti-oxidation, corrosion resistant, anti-rust, anti-deformed and fadeless, so it will have a long lifespan. What this bolt can offer you is that can be easy to install with the highly compatible feature, it can lock the chain wheel tightly which can provide the safety while riding bike. Made of aluminum alloy, this chainring bolt is ultra light. The inner diameter of this bolt is 4.9mm, outer diameter is 12mm, the height is 9.6cm. It is suitable for MTB, mountain bike, folding bike and so on. Item Name: Chainring Bolt Material: Aluminum Alloy Features: Corrosion Resistant, High Hardness, Anti-oxidation Size Details: Inner Diameter: 0.49cm/0.19" (Approx.) Outer Diameter: 1.2cm/0.47" (Approx.) Height: 0.96cm/0.38" (Approx.) Notes: 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. Package Includes: 5 x Chainring Bolts