Window Rpm Activated Switch These Rpm-Activated Switches Will Perform A Variety Of Different Functions From Turning On A Bulb Or Solenoid To Activating An Timing Control At A Desired Rpm MSD IgnitionThe RPM Window Switch, PN 8956, has two rpm adjustments one to activate a circuit, while the other deactivates the same circuit. This Switch will supply then remove ground to a circuit. This is a great feature to deactivate nitrous before the engine's rev limit is reached. Both Switches can be used with stock inductive ignitions or an MSD Ignition and can handle up to 1. 5 amps. No rpm modules are supplied. The RPM Activated Switch, PN 8950, has two