Wheel Balancer CB-3550 is a professional, commercial grade wheel balancer for busy auto repair shop, car dealerships. With this wheel balancer, 3-Data are entered manually. Dynamic Mode is for balancing steel wheels by placing clip on weights on both the inside and outside of the rim. In Static Mode, everything functions the same as in Dynamic mode except balancing the wheel by placing weight on the outside of the rim. ALU1-3 Modes allow the wheel balancer CB-3550 to accommodate diversified structure of ALU wheels by placing stick and/or clip on weights on proper position of the wheels, which do not accept clip on weights on one side or both sides. ALUS1-2 Modes will be the most accurate modes when using stick on weight by entering 4 parameters. Motorcycle Mode allows this wheel balancer to balance motorcycle wheel. An extra adapter for the wheel balancer should be purchased separately. OPT Function is used to optimize the best mating of tire and wheel when unbalancing value is big, and you do not want to put much weight to balance your wheel.