Spark Plug Caliper, Spark Plug Gap Tool Universal Spark Plugs Gapper Gapping Kit Compatible with Most 10mm 12mm 14mm 16mm Spark Plugs, Red

My product came a little defected but easily fixed.The knob used to size the gap was screwed down so tight and bottomed out when I backed the gapping tool the knob came off the tread. Used super glue and bonded it back now it works

So far this product looks like the high dollar ones on the market. I havent tried it yet to gap some plugs but so far it looks and operates as it should. I've seen similar ones got for $100+. The screw adjustment works fine. I put a little oil on the threads before tightening the adjuster.

does not work on the smaller spark plugs for chains saw , works for generator , long spark plugs only