Screw thread limits chart

Major, pitch, and minor diameter limits for Class 2A and 3A external screw threads.

0.9982 0.9868 0.9459 0.9441 0.9382 0.8960
1 -12 3A 1.0000 1.0000 0.9886 0.9459 0.9459 0.9415 0.8978
1-1/8-7 2A 1.1250 1.1228 1.1064 1.0322 1.0300 1.0228 0.9475
1-1/8-12 2A 1.1250 1.1232 1.1118 1.0709 1.0691 1.0631 1.0210
1-14-7 2A 1.2500 1.2478 1.2314 1.1572 1.1550 1.1476 1.0725
1-1/4-12 2A 1.2500 1.2482 1.2368 1.1959 1.1941 1.1879 1.1460
1-3/8-6 2A 1.3750 1.3726 1.3544 1.2667 1.2643 1.2563 1.1681
1-3/8-12 2A 1.3750 1.3731 1.3617 1.3209 1.3190 1.3127 1.2709
1-1/2-6 2A 1.5000 1.4976 1.4794 1.3917 1.3893 1.3812 1.2931
1-1/2-12 2A 1.5000 1.4981 1.4867 1.4459 1.4440 1.4376 1.3959
1-3/4-5 2A 1.7500 1.7473 1.7268 1.6201 1.6174 1.6085 1.5019
2 – 4-1/2 2A 2.0000 1.9971 1.9751 1.8557 1.8528 1.8433 1.7245