6M-2L Marine Certified With Rev Limit Ul Approved For Marine Use, Includes Built-In Rev Limiter MSD IgnitionThe MSD 6M 2L Ignition Control is designed for performance marine applications where a high energy and reliable ignition is a necessity. The capacitive discharge (CD) design of the MSD produces full power sparks throughout your boat's entire rpm range. Below 3,000 rpm, a series of multiple sparks burn in the cylinder for 20 Degree of crankshaft rotation ensuring complete combustion. Together, these sparks produce easier starting, great throttle