Thread Milling Tools UN (UNC, UNF, UNEF) INTERNAL ANSI B1.1-1982 UN NUT 1/4P 60 1/8P UN SCREW STRAIGHT FLUTES THREAD SIZE PITCH ORDERING L L1 D1 D2 NO. OF COARSE FINE EXTRA FINE TPI CODE FLUTES UNC UNF UNEF 1 1/4" 5/16" 32 TMX06059L14 32UN 57 14.0 6 5.9 3 2 28 TMX06051L12 28UN 57 12.2 6 5.1 3 3 5/16" 7/16"-1/2" 28 TMX08079L15 28UN 63 15.8 8 7.9 4 4 1/4" 24 TMX06059L10 24UN 57 10.8 6 5.9 3 5 7/16" 20 TMX06048L12 20UN 57 12.0 6 4.8 3 6 1/2" 20 TMX08079L19 20UN 63 19.7 8 7.9 3 7 5/16" 20 TMX10099L17 20UN 73 17.5 10 9.9 4 8 9/16"-5/8" 18 TMX06057L16 18UN 57 16.0 6 5.7 3 9 3/8" 18 TMX08079L18 18UN 63 18.5 8 7.9 3 10 3/4" 16 TMX08068L18 16UN 63 18.2 8 6.8 3 11 7/16" 16 TMX12119L26 16UN 84 26.2 12 11.9 4 12 7/8" 14 TMX08078L20 14UN 63 20.8 8 7.8 3 13 1/2" 14 TMX12119L24 14UN 84 24.5 12 11.9 4 14 9/16" 13 TMX10093L24 13UN 73 24.4 10 9.3 3 15 1 12 TMX12119L27 12UN 84 26.4 12 10.6 4 16 5/8" 12 TMX16159L39 12UN 105 39.1 16 15.9 5 17 3/4" 11 TMX12115L31 11UN 84 31.1 12 11.5 4 18 7/8" 10 TMX16143L36 10UN 105 36.8 16 14.3 4 19 1 9 TMX16159L40 9UN 105 40.9 16 15.9 4 20 8 TMX20197L39 8UN 105 39.7 20 19.7 4 24