By using centrifugal force the free moving weights (durametal and synthetic fluid) sealed in the balancer automatically distributes to exactly where needed, placing the assembly in equilibrium or perfect balance. When a sprung assembly is out of balance, deflection is caused via the springs or tire sidewalls. These free moving weights sense this deflection and move opposite the heavy points to balance the entire assembly, wheels, tires, drums, hubs, even mud, snow or ice stuck to the wheels.