【Compatible with】:The RC Upgrades Part for 1/10 BIG ROCK 3S 4X4 RTR（ARA4312V3，ARA102723） 1/10 GRANITE 3S 4X4 RTR（ARA102720，ARA4302V3） 1/10 GRANITE 4X4 RTR BRUSHED（ARA4202XV3，ARA4202V3） 1/10 KRATON 4S 4X4 RTR（ARA102690） 1/10 OUTCAST 4S 4X4 RTR（ARA102692） 1/10 SENTON 3S 4X4 RTR（ARA102721，ARA4303V3，ARA4203XV3，ARA4203V3） 1/10 VORTEKS 3S 4X4 RTR（ARA4305V3） 1/8 TYPHON 3S 4X4 RTR（ARA102722，ARA4306V3） 【High precision】:The gear set is with precision manufactured gear teeth for smooth, consistent performance,they works with low noise. 【Long-lasting Performance】:We provide 2 different teeth pinion gear 3.17mm and 5.0mm Pinion Gear Sets (20/21T ) to make you more choice in gear ration. 【Easy to Install】:Easy to install, great for replace the old or broken part.Increase overall performance and durability of your RC car. 【Special note】:In the position of various screw holes, screw glue is applied, so that the screws are not easily separated from the upgrade accessories. hopsupRC RC 57T with 20T/21T Pinions Spur Gear Slipper Clutch (0.8) Pitch Gear Upgrades Part for 1/10 Senton Granite Vorteks Big Rock 3S BLX,Kraton Outcast 4S BLX,1/8 Typhon 3S BLX.Red