[HIGH PERFORMANCE------ Teeth: 52T. The crank arm length is 170mm fit for single speeds mountain bike It is a great bike replacement for your old or worn part. ------ Size: 30. 00X22. 50X2. 00 cm/ 11. 79X8. 84X0. 79 inch Make of iron material high strength and durability. ------ Chain Size: Standard 1/ 2 X 3/ 32 HIGH CARBON STEEL------ High carbon steel crank and high carbon steel crankset high strength not easy to deform durable EASY TO INSTALL------ Bicycle high- carbon steel crankset easy to install and simple to operate]