This part is a critical, high-precision transducer used for measuring combustion knock in octane rating engines. Item: D-1 Detonation Pickup (Transducer) Application: Used for Octane Testing (Research D2699 and Motor D2700 methods) Compatible Equipment: Waukesha CFR F1/F2 Octane Rating Units Function: Detects combustion pressure changes (detonation) within the engine cylinder and sends signals to the detonation mete