MSD 87441 4000 Series Module Kit, Odd Increments, Kits include five modules

MSD Ignition 87441 RPM Module Kit

MSD 8744 4000 Series Module Kit, Even Increments

MSD Ignition RPM Module Kit for 4100-4900 RPM, 200 RPM Increments - Part 87441

MSD IGNITION 4100-4900 RPM Odd Series Module Kit- 87441

MSD 87441 Ignition RPM Modules 4100 to 4900 rpm Set of 5

MSD 87481 8000 Series Module Kit, Odd Increments

MSD Ignition RPM Module Kit 4100-4900 RPM for Performance Engines