The 17-tooth (1.0 metric pitch) clutch bell is made from durable steel for long-lasting performance. Includes 5x8x.5 mm fiber washer and 5 mm E-clips (2). Clutch bells are available in a variety of sizes to fine-tune your truck's gear ratios for more torque or higher top speed. (Requires two 5x10x4 mm ball bearings.)