The JIS tapered thread is similar to the BSPT connection in design, appearance and dimensions. The JIS tapered thread and the BSPT connection are interchangeable.
Inch Size, Size mm (Dash), Nominal Thread Tapered Size, Male Thread O.D. Female Thread I.D.
1 ⁄ 4 6 (04) 1 ⁄ 4 -19 33 ⁄ 64 13,2 15 ⁄ 32 11,9
3 ⁄ 8 9 (06) 3 ⁄ 8 -19 21 ⁄ 32 16,7 19 ⁄ 32 15,3
1 ⁄ 2 12 (08) 1 ⁄ 2 -14 13 ⁄ 16 21,0 3 ⁄ 4 19,2
3 ⁄ 4 19 (12) 3 ⁄ 4 -14 1 1 ⁄ 32 26,4 31 ⁄ 32 24,6
1 25 (16) 1-11 1 5 ⁄ 16 33,3 1 7 ⁄ 32 30,9
1 1 ⁄ 4 32 (20) 1 1 ⁄ 4 -11 1 21 ⁄ 32 41,9 1 9 ⁄ 16 39,6
1 1 ⁄ 2 38 (24) 1 1 ⁄ 2 -11 1 7 ⁄ 8 47,8 1 25 ⁄ 32 45,5
2 50 (32) 2-11 2 11 ⁄ 32 59,7 2 1 ⁄ 4 57,4
