Replacing this high wear item with a new, high quality Sprocket, means that it will fit perfectly, the pitch and machining will be exactly to specification, and the heat treatment and hardening process will be exactly right, to ensure even wear on both this and the final Drive chain.
When replacing this try where possible to renew rear Sprocket and Drive chain at the same time - mixing part worn items with new can cause premature wear of the new parts! Order all the items required at the same time and pay just one low shipping cost.