Description:The design of positive and negative teeth eliminates the need to install chain guides, and there is no need to worry about losing the chain. It is suitable for bikes, road bikes, mountain bikes.Featuring good toughness, it is not easy to deform and rust. CNC craftsmanship brings good intensity and long using time.Made of high quality aluminum alloy material, the product is sturdy, wear-resistant and durable.The length of the product is 12cm, the width is 12cm, and the thickness is 0.4cm.It's suitable for bicycle, mountain bike, road bike, etc. It is compatible with M370/M610 crank.Item Name: Positive Negative ChainringMaterial: Aluminum AlloyCraft: CNCSpecification: 30TColor: Black, Red, BlueFeatures: Wear-resistant, CNC Craftsmanship, Easy to InstallSize Details: BCD: 104mm/4.09" (Approx.)Size: 12cm x 12cm x 0.4cm/4.72" x 4.72" x 0.16" (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:1 x Bike Chainring