Lisle 50850 Ignition Spark Tester
- A handy tool to check ignition spark without removing the spark plug..
- The tool is specially calibrated to measure ignition voltage..
- Works on both standard and electronic ignition systems. Easy to use..
- Simply adjust calibration screw to proper gap size..
- Attach spark plug wire to end of tester..
- Clamp tester on engine to ground. Crank engine and check for spark..