For automotive vehicle applications that include an OAP as Original Equipment.
Dayco OAPs are engineered with one-way clutches that allow the rotational inertia of the alternator to “overrun” during any belt deceleration event. Dayco OAPs, which are designed for long service life, decrease drive belt vibration and reduce belt slippage during rapid acceleration or deceleration, resulting in less stress on the drive belt and other accessories as well as increased alternator and drive belt life. Dayco OAPs are application-specific replacement parts. If a vehicle requires an OAP, the same type of pulley must be installed using the proper tools.