0000-160 3B Plug Gage UNS stands for (American) “National Standard” miniature Thread series. This gage is one piece handle containing "Go" Precision Thread Gage made of High Speed Steel then hardened. Please note that this gage is made to the tighter 3B Picture is representative of this item in our stock. Brand is;" MiniTaps" made specifically for us in Switzerland. Factory measurements as our cert included in price.