Sierra Mercruiser & OMC Ignition Electronic Conversion Kit #18-5297 Fits: Mercruiser & OMC Sterndrive/Cobra 4 cylinder GM Standard: Replaces points and condenser for true solid state ignition. Uses standard Coil, Cap, Rotor. Easy to install, one piece, 2 wire hook-up. Accurate to within 1/4' timing accuracy 0-6000 RPM range. Hi-performance:Senses current levels in the coil and adjusts the dwell to maintain peak energy throughout the entire RPM range. Develops on average 4 times more available energy between 3000 and 5000 RPM's and twice as much plug voltage as point type systems. Ignition energy is sustained and coil life is increased when peak current level is reached just prior to spark. More stable timing. Use with 18-5472 'Flame thrower II' coil for optimum performance.