This is a ProTek R/C Flywheel Nut, Collet and Shim Set, and is intended for use with 1/8 Scale Nitro Engines. Having the proper shims for the job is important. You don't want too much play or too little. This ProTek R/C Flywheel Nut, Collet and Shim Set is sure to have what you need to get it just right.
Includes: