Bolt Depot Threads Per Inch Table for US Bolts
US Threads Per Inch Table Print this page Bolt Size Threads Per Inch TPI Coarse Thread UNC Fine Thread UNF 0000 160 000 120 00 90 0 80 1 64 72 2 56 64 3 48 56 4 40 48 5 40 44 6 32 40 8 32 36 10 24 32 12 24 28 1 4 quot 20 28 5 16 quot 18 24 3 8 quot 16 24 7 16 quot 14 20 1 2 quot 13 20 9 16 quot 12 18 5 8 quot 11 18 3 4 quot 10 16 7 8 quot 9 14 1 quot 8 12 1 1 8 quot