Check the listing for details. 6564 MSD Digital 6M-3L Marine Ignition. Condition: New, Made in US. Listed at 599.95 USD. Marine certified, digital capacitive discharge ignition with built-in rev limiter and start retard.. Three rotary dials and an LED display simplfy setting the cylinder select, start retard and rev limiter. Plug-in rev limiter chips and hard to read dials are a thing of the past. For diagnostic purposes, the LED display can also be set to a live tach mode on V8's and even display battery voltage with the turn of a knob. We've raised the bar and added an all-new UL listed marine ignition box to our lineup. The 6M-3L is a fully sealed unit with a single wiring connector makeing installation neat and easy. The 6M-3L is a capacitive discharge ignition that multi-sparks from idle to 3,000 RPM providing a clean idle and quick throttle response.