1.20UNM Plug "Go" Gage pitch .25mm; UNM stands for “United National Miniature” the American Metric miniature Thread standard. This gage is one piece handle containing Go Precision Thread Gage made of High Speed Steel then hardened. Class of fit 1.20UNM is similar to metric 6g for M1.2 thread. Picture is representative of part, Brand is;" MiniTaps" made specifically for us in Switzerland.
We have a long form cert available on this Gage.