The MSD LED Shift Light lights up to remind the driver to shift once the engine reaches a programmed RPM, using the same plug-in modules as the MSD Soft Touch Rev Control. It plugs directly into the tach output on MSD 6, SCI, 7, 8, and 10 Series Ignitions, or connects to the negative coil terminal on points or inductive-type ignitions, and works on 2, 4, 6, or 8-cylinder engines.Specifications: Brand: MSD Category: Body Product Type: Shift Lights Sub Category: Instrument Panel Warning: California Proposition 65 Warranty: Manufacturer's Limited 1 Year Warranty Part Number: 8952 Housing measures 4.5"L x 3.5"H with a 1.5" diameter lens. RPM modules are sold separately.FAQHow does the MSD 8952 Shift Light connect to my ignition?It plugs directly into the tach output on MSD 6, SCI, 7, 8, and 10 Series Ignitions, or wires to the negative coil terminal on points or inductive-type ignitions.Does the 8952 include RPM modules?No, RPM modules that set the activation point are sold separately.What engines is the 8952 compatible with?2, 4, 6, or 8-cylinder engines.{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"How does the MSD 8952 Shift Light connect to my ignition?","acceptedAnswer":{"@type":"Answer","text":"It plugs directly into the tach output on MSD 6, SCI, 7, 8, and 10 Series Ignitions, or wires to the negative coil terminal on points or inductive-type ignitions."}},{"@type":"Question","name":"Does the 8952 include RPM modules?","acceptedAnswer":{"@type":"Answer","text":"No, RPM modules that set the activation point are sold separately."}},{"@type":"Question","name":"What engines is the 8952 compatible with?","acceptedAnswer":{"@type":"Answer","text":"2, 4, 6, or 8-cylinder engines."}}]}