Bring your coil-in-cap style GM HEI to life. Mallory's high output HEI module offers more performance and features than any other module available. Easy to adjust rev limiting from 4000 to 8500 RPM. Special extended dwell circuitry insures a hotter spark over a broader RPM range. Reduces high RPM retard commonly found with other HEI modules. Works on 4, 6 and 8 cylinder coil-in-cap distributors with 4 pin modules