Magneto, Pro Mag Lite, Billet Aluminum Housing, Polished Finish, Bronze Gear, Ford, 351W, Each MSD took their original Pro Mag 12 distributors, added some new features to build performance, and subtracted 3 lbs. to help you get down the track faster. The results are the Pro Mag Lites. They utilize a magnetic pickup design with 16 rare earth magnets for rock-steady performance without recharging. They deliver 12 amps and 40,000 V worth of spark energy, feature built-in rev control that's good for up to 12,000 rpm, and use an all-billet housing for superior durability. They're compatible with MSD's crank trigger system.