JT Sprockets JTR1220.38 38-Tooth Steel Rear Sprocket Made from C49 high carbon steel Heat treated and hand finished to meet or exceed OEM standards Outlasts any mild steel or surface hardened sprocket Each sprocket goes through 10 quality control checks before it leaves the factory 39 Tooth Steel Rear Sprocket Made from C49 high carbon steel Heat treated and hand finished to meet or exceed OEM standards Outlasts any mild steel or surface hardened sprocket Each sprocket goes through 10 quality control checks before it leaves the factory 38 Tooth Steel Rear Sprocket