Perfect for gear drive camshafts. Consistent balance and precision machining. Balance gear is installed for easy installation. Strong assembly eliminates need to weld crankpin. Heat treated 4140 material is harder and twice as stong as stock. Connecting rods are designed with Finite Element Analysis (FEA) to eliminate weak spots. Includes flywheel, crankpin and connecting rods. Made in the USA. Fits All M8 Models With Balancer Gear And Full Wrist Pin.