MSD 89952 RPM Chip Tester

If you are using a MSD ignition box or RPM module, you need to have this RPM checker. It is simple to use as you just plug it in to your ignition box or RPM module and hold down one button. Limits MSD box to 3000 RPM if box is used correctly.

• Essential for any racing class with RPM limitations
• Test MSD box or RPM module
• Simply plug-in and hold button
• 9V battery included