Lightweight design, CNC turning, tight and delicate threads Colored by vacuum electroplating High-Quality Material: Crafted from premium aluminum alloy , MUQZI chainring bolts offer exceptional durability and corrosion resistance, ensuring long-lasting performance in all weather conditions. 8.5mm for double chainrings, making them suitable for a wide range of road and mountain bikes. Easy Installation: Designed for hassle-free installation, these chainring screws can be quickly and securely attached to your bike, enhancing your cycling experience without the need for professional help. 5-piece set to best suit your bike's requirements and ensure optimal performance. Specifications Material: Aluminum Alloy Color:Black/Red/Gold/Purple/Blue Size: 8.5 x 9.5 x 12mm Package Contents: 5Pcs Chainring Bolts Set 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.