MSD Ignition 87431 RPM Module Kit Revolution LimiterEngine Ignition RPM Governor RPM Module Kit Revolution Limiter RPM Module Kit Revolution Limiter; 3100 3900 RPM; Odd Increments; SPECIFICATIONS: WARNING CA Proposition 65: Yes WARNING CA Proposition 65 Message: WARNING: Cancer and Reproductive Harm www. P65Warnings. ca. gov FEATURES: Five Modules Provided 200 RPM Increments; Odd From 3100 3900 RPM Each kit is within a 1,000 rpm range. For example, the PN 8745 is supplied with: 5,000, 5,200, 5,400,