T-Works engine bearing replacement tool
T-Works have created these engine bearing replacement tools for both .21 and .12 engines. Presented in a handy protective carrying case, the complete tool does exactly what you expect it to, helping you remove and replace the main bearing from your engine. The bearing puller and collets are available as a set allowing you to use the tool for both engine types. The collets are also available separately with a 14mm, 12mm and 11.8mm version available as well as the pressure adaptors available separately for .21 and .12 engines.
Source: T-Works [rc-tworks.com]