It is the quickest way to test for no-start conditions, test if the spark plug is getting the spark and to see how strong it is.
Can be used on all kinds of engine which equipped with ignition coil. Car, motorcycle, 2-cycle small engines trimmer / chainsaw… 4-cycle engines lawn mower / tractor, etc.
High visibility white lettering makes it easy to read the gap measurement from 0 to 40k
Standard plug wire tip and can be unscrewed so the tester can be used on small engines and some motorcycles
Added a spring to the tightening bolt which keeps secure and stays where you put it
It is the quickest way to test for no-start conditions, test if the spark plug is getting the spark and to see how strong it is.
Can be used on all kinds of engine which equipped with ignition coil. Car, motorcycle, 2-cycle small engines trimmer / chainsaw… 4-cycle engines lawn mower / tractor, etc.
High visibility white lettering makes it easy to read the gap measurement from 0 to 40k
Standard plug wire tip and can be unscrewed so the tester can be used on small engines and some motorcycles
Added a spring to the tightening bolt which keeps secure and stays where you put it

How does this connect to a coil on plug system
Grip the clip to the engine. Put the other end in the spark plug wire. Read the length on the spark through the little window.
The longer the spark gap the stronger the coil.

Specifications:
SE means small engine that puts out less spark.
20 is .020 inches
30 is .030 inches.
40 is .040 inches
Check your engine manual which may tell you what your engine is supposed to put out