UNC United American made coarse thread
UNF United American fine thread
Special screw thread of a unified American UNS
American unified taps are 60 degrees
For example: 4-40UNC, nominal diameter 2.845mm, the number of teeth per inch 40, UNC coarse teeth, pitch 0.635;
7/16-20UNF, nominal diameter 11.112mm, the number of teeth per inch 20, UNF fine teeth, pitch 1.27;
The price tag is 1。
Please pay attention to the purchase, must be digital and English are right on the fit!
The default freight is the first heavy, large tap overweight need to make up the shipping after shipment, thank you!