High-Speed Nut Taps / H-SNT
Unified coarse thread
TAP SIZE A B   C FLUTE
NO. 6-32 UNC 62.0 19.0 24T 2.4 3
NO. 8-32 65.0 19.0 24T 3.1 3
NO. 10-24 UNC 65.0 25.0 24T 3.4 3
NO. 12-24 UNC 65.0 25.0 24T 4.0 3
1/4-20 UNC 77.8 28.0 22T 4.6 3
1/4-20 UNC 77.8 30.0 24T 4.6 3
5/16-18 UNC 77.0 35.0 24T 6.0 5
3/8-16 UNC 89.0 40.0 24T 7.3 5
7/16-14 UNC 102.0 47.0 24T 8.6 5
1/2-13 UNC 102.0 50.0 24T 10.0 5
9/16-12 UNC 114.0 54.0 24T 11.0 5
5/8-11 UNC 127.0 59.0 24T 12.8 5
3/4-10 UNC 133.0 64.0 24T 15.0 5
7/8-9 UNC 140.0 72.0 24T 17.0 5
1"-8 UNC 165.0 80.0 24T 20.0 5

Unified fine thread
TAP SIZE A B   C FLUTE
NO. 10-32 UNF 67.0 19.2 24T 3.8 3
NO.12-28 UNF 69.8 22.0 24T 4.2 3
1/4-28 UNF 77.8 22.0 24T 4.8 3
5/16-24 UNF 77.0 28.0 24T 6.3 5
3/8-24 UNF 89.0 29.0 24T 8.0 5
7/16-20 UNF 102.0 34.0 24T 9.0 5
1/2-20 UNF 102.0 34.0 24T 10.0 5
9/16-18 UNF 114.0 37.0 24T 11.4 5
5/8-18 UNF 127.0 37.0 24T 13.1 5
3/4-16 UNF 133.0 42.0 24T 15.0 5
7/8-14 UNF 140.0 48.0 24T 18.0 5
1"-12 UNF 165.0 55.0 24T 21.0 5