Davis Unified Ignition (DUI) 81720BK street/strip distributor for Cadillac 368, 425, 472, and 500 ci. engines eliminates the need for an external coil or additional ignition control box. The single 12-volt wire connection cleans up the underhood wiring and the 50,000-volt coil along with the calibrated mechanical advance curve and included vacuum advance provide a crisper throttle response and increased power over the original distributor.