This is a replacement ProTek R/C 0.2mm Samurai 321B Head Gasket. This aluminum gasket is used to adjust and fine tune the compression (deck height) of the engine. In general the higher the nitro percentage of the fuel you run, the more head shims you should put in your engine. From the factory, the Samurai 321B comes installed with one 0.1mm and one 0.2mm shim.
This product was added to our catalog on November 6, 2014