Distributor Cap and Rotor Kit for MerCruiser V8 Thunderbolt IV or V HEI ignitions Fits: All GM 5.0L, 5.7L, 7.4L, 8.2L V8 engines with Thunderbolt Ignition IV or V HEI ignitions from early 1980's to early 2000's Replaces Part #: 805759Q3, 805759T3, 18-5273, 71780 The distributor cap and rotor meets or exceeds factory specifications and is a direct replacement