The function of attenuator in fiber optic system is to reduce the optical power in the fiber. The most common application of the attenuator is to balance the optical power between multi-fiber systems and to reduce the receiver saturation that limits the system performance. FO Attenuator Fiber Optic Attenuator FC, SC/APC, ST, LC, MU, FC/APC, SC, LC/APC plug type fiber optic attenuators.