Digital coating thickness gauge.
Fullsize image: https://diqn32j8nouaz.cloudfront.net...1_fullsize.jpg
https://diqn32j8nouaz.cloudfront.net...1_fullsize.jpg
Previously:
https://www.homemadetools.net/forum/...986#post160486
https://www.homemadetools.net/forum/...902#post232704
https://www.homemadetools.net/forum/...328#post135144
https://www.homemadetools.net/forum/...310#post142200
https://www.homemadetools.net/forum/...908#post160181
