This handy spark plug gap tool measures precise gaps. It is safe with no risk of electrode damage and eliminates misfires and error codes due to inaccurate gaps on your spark plugs. The gap tool is magnetic, preventing any slipping while you work.

Features:
Compatible with most 10mm, 12mm, and 14mm threaded spark plugs.
Color :  Blue
Steel adjuster knob
Aluminum anodized

Feeler Gauge:
Number Of Pieces: 32
Range: 0.04-0.88mm (0.0015-0.035inch)
Metric sizes (mm): 0.04, 0.05, 0.06, 0.08, 0.10, 0.13, 0.15, 0.18, 0.20, 0.23, 0.25, 0.25, 0.28, 0.30, 0.33, 0.35, 0.38, 0.40, 0.43, 0.45, 0.48, 0.50, 0.53, 0.55, 0.58, 0.60, 0.63, 0.65, 0.70, 0.75, 0.80, 0.88
Inch sizes: 0.0015, 0.002, 0.0025, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.010, 0.010, 0.011, 0.012, 0.013, 0.014, 0.015, 0.016, 0.017, 0.018, 0.019, 0.020, 0.021, 0.022, 0.023, 0.024, 0.025, 0.026, 0.028, 0.030, 0.032, 0.035
Warm notice: there is some anti-rust oil on the stainless steel feeler gauge to prevent it from rusty, please don’t worry about that

Instructions:
Screw your spark plug into the bottom of our gap tool
Use your desired size feeler gauge for gap thickness.
Turn the knob with the feeler gauge in place till the side electrode compresses to the desired gap thickness.
NOTE: It is normal for some spark plugs electrode spring back. If they do spring back we suggest using a measurement 2mm less than what you are aiming for. For example,  if 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. 
The Ruler Is Preferably Spring Alloy Steel With Full Toughness
Overall Heat Treatment, Good Elasticity, High Hardness And Wear Resistance, Long Life
Surface Polishing Treatment, No Burrs On The Edge Of The Ruler, No Hand Injury When Touched
Can Be Rotated 360 Degrees, Easy To Expand And Contract
Screw Fixation And Adjustment, Single Piece Disassembly Operation Is More Convenient
The Ruler Has Metric And Imperial Corresponding Specifications To Use More Clearly

Includes:
1 x Spark Plug Gap Tool
1 x Feeler Gauge