Thread geometry - Unified Extra Fine (UNEF)

 

All dimensions in mm unless otherwise stated.

 

d1 - Minor thread diameter male

d2 - Minor thread diameter female

d3 - Pitch diameter

d4 - Major diameter
 
Thread Major diameter Thread per inch Pitch diameter Minor diameter male thread Minor diameter female thread
No 12 0.2160 32 0.1957 0.1788 0.1822
1/4 0.2500 32 0.2297 0.2128 0.2162
5/16 0.3125 32 0.2922 0.2753 0.2787
3/8 0.3750 32 0.3547 0.3378 0.3412
7/16 0.4375 28 0.4143 0.3949 0.3988
1/2 0.5000 28 0.4768 0.4574 0.4613
9/16 0.5625 24 0.5354 0.5129 0.5174
5/8 0.6250 24 0.5979 0.5754 0.5799
11/16 0.6875 24 0.6604 0.6379 0.6424
3/4 0.7500 20 0.7175 0.6905 0.6959
 
Thread Major diameter Thread per inch Pitch diameter Minor diameter male thread Minor diameter female thread
13/16 0.8125 20 0.7800 0.7530 0.7584
7/8 0.8750 20 0.8425 0.8155 0.8209
15/16 0.9375 20 0.9050 0.8780 0.8834
1 1.0000 20 0.9675 0.9405 0.9459
1 1/16 1.0625 18 1.0264 0.9964 1.0024
1 1/8 1.1250 18 1.0889 1.0589 1.0649
1 3/16 1.1875 18 1.1514 1.1214 1.1274
1 1/4 1.2500 18 1.2139 1.1839 1.1899
1 5/16 1.3125 18 1.2764 1.2464 1.2524
1 3/8 1.3750 18 1.3389 1.3089 1.3149
 
Thread Major diameter Thread per inch Pitch diameter Minor diameter male thread Minor diameter female thread
1 7/16 1.4375 18 1.4014 1.3714 1.3774
1 1/2 1.5000 18 1.4639 1.4339 1.4399
1 9/16 1.5625 18 1.5264 1.4964 1.5024
1 5/8 1.6250 18 1.5889 1.5589 1.5649
1 11/16 1.6875 18 1.6514 1.6214 1.6274