PQY Universal Spark Plug Gap Tool Compatible with Most 10mm 12mm 14mm 16mm Spark Plugs Red.

Simple steps for easy installation:1. Simply place your spark plug into the gap tool. 2. Use your desired size feeler gauge for gap thickness. 3. Turn the knob with the feeler gauge in place till the side electrode compresses to the desired gap thickness. NOTE: Some spark plugs electrode will spring back This is normal for some spark plugsIf your gap target is 0. 44mm we suggest to use 0. 42mm this way when it spring back you will get it to 0. 44mm. Please note that will vary on every spark plug brand, manufacturer, material of the spark plug.