AN SizeMetal Tube O.D.Thread Size
2 1/8" 5/16-24 SAE
3 3/16" 3/8-24 SAE
4 1/4" 7/16-20 SAE
5 5/16" 1/2-20 SAE
6 3/8" 9/16-18 SAE
8 1/2" 3/4-16 SAE
10 5/8" 7/8-14 SAE
12 3/4" 1-1/16-12 SAE
16 1" 1-5/16-12 SAE
20 1-1/4" 1-5/8-12 SAE
24 1-1/2" 1-7/8-12 SAE
28 1-3/4" 2-1/4-12 SAE
32 2" 2-1/2-12 SAE