Features: CNC machining integrated, intensity is more secure, appply for long time cycling Extended edition plus or minus tooth shape, the chain can effect better Can be used with many accessories for mountain bikes and can be combined with a variety of configuration options Wide,Hollow Design,Ultralight. Adopts aluminum alloy CNC cutting to ensure the accuracy of product use. Material is aluminum alloy, hardness is much higher than the originals steel chain wheel, strong and practical.