الوصف

It is usually mounted at the front end of the crankshaft in order to absorb and dissipate the majority of the vibration energy. 
Normally, the harmonic damper is made up of three parts. The inner part is bolted to the crankshaft. The center part is a rubber ring which dampens crankshaft vibrations, and the outer part with the timing marks and pulley cuts for the belts. 
It is the rubber which is balanced to eliminate rotational unbalance of the engine which will cause a vibration in the car