The MSD Blaster 3 coils put out 45,000 volts, 15,000 more than stock. They also have an oil-filled metal canister and fit stock mounting brackets. The coils have a unique Power Tower that is twice as high as a standard tower. The extra distance prevents secondary arcing betweeen the primary terminals and the coil center. The HEI-style boot and terminal keep the coil wire secure.