For M8 models Allows you to check engine oil pressure using a quality liquid filled mechanical psi gauge while keeping your factory electronic gauge and or low oil pressure indicator light hooked up Hooks up to the engine case via the pressure port to the oil filter, remove the factory 1/4 NPT plug and install the Feuling fittings, oil line routes up the right side frame rail, gauge fastens to the handlebars near the master cylinder. GAUGE OIL PRESSURE M8 SL