Sierra 18-5289 Hi Performance Conversion Kit Senses current levels in the coil and adjusts the dwell to maintain peak energy throughout RPM Range; Develops, on average, 4 times more available energy between 3000 and 5000 RPM's; Develops, on average, twice as much plug voltage as point-type systems; More stable timing; Use with 18-5472 "Flame Thrower II" Coil for optimum performance; Ignition energy sustains/coil life increased when peak current level is reached prior to spark; Resistance Ohms: 0.6Fits most Prestolite V-8 Distributors w/ screw down capUse with: 18-5472 Hi-Performance Ignition Coil;