CDI Electronics offers excellent ignition and diagnostic solutions. They ensure engine users and manufacturers have the best quality equipment. The switch box keeps track of the trigger voltages for each ignition circuit. The switch box establishes a threshold voltage, and when it reaches its value, it discharges a capacitor to the ignition coil. As the magnet approaches a trigger coil, the trigger voltage of the coil climbs and peaks as the electromagnet approaches the coil's top. The attraction moves away from the solenoid, then voltage reverses. The growing voltage is critical. Key Features: High-performance ignition pack replacement The mounting plate connected to the CDI switch box and ignition coil offers ease in installation On-board is simple yet incredibly effective Specifications: Brand: CDI Electronics SKU: 114-5713 UPC: 736983850621 Weight: 0.80 lbs Fits: 2 Stroke Engines between 1997-2005 - 6, 8, 10, 15, 20, and 25 Horsepower Product Measurement: 5 x 4 x 2 inches Country of Origin : USA Application: Mercury-Mariner Manufacturer Part Number (MPN): 114-5713 Replaces Products: 667-1145713, 736983850621 1997-2006 (6,8,9.9,10,15,20 & 25HP) 2 Stroke Engines w/ 4 magnet Flywheel