[Fits For]: Arrma 1/10 Senton Granite Big Rock Vorteks [Long-lasting Performance]: Made of Metal. The tough molded composite material for long-lasting durability .Precision manufactured gear teeth for , consistent performance. [High precision]The gear set is with precision manufactured gear teeth for , consistent performance, they works with low noise. [21T 19T 17T Gear for Choices]The speed depends on ratio. We provide 3 different teeth pinion gear (17T 19T 21T) to make you more choice in gear ratio. Material: Metal colour: 3-Dark blue Package Contents: 1 x clutch gear 1 x 17T Pinion Gear 1 x 19T Pinion Gear 1 x 21T Pinion Gear Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.