Threading Inserts UN ( UNC, UNF, UNEF ) INTERNAL ANSI B1.1-1982 BBA A UN NUT 1/4P 60° L L 1/8P UN SCREW I.C. I.C. MULTITOOTH STANDARD STANDARD PITCH CATALOG NUMBER DIMENSIONS TPI RIGHT HAND LEFT HAND Lmm I.C. A B 7 UN 7 IR22 UN 7 IL22 1.6 2.3 6 UN 6 IR22 UN 6 IL22 22 12.70 1.6 2.3 5 UN 5 IR22 UN 5 IL22 1.7 2.4 4.5 UN 4.5 IR27 UN 4.5 IL27 1.8 2.6 27 15.875 4 UN 4 IR27 UN 4 IL27 2.0 2.8 MULTITOOTH PITCH TEETH CATALOG NUMBERRIGHT HAND ANVIL LTPImm DIMENSIONSI.C.A B 20 2 UN20 2M IR16 1.6 2.6 16 2 UN16 2M IR16 1.6 2.4 IS16M 16 9.525 14 2 UN14 2M IR16 2.2 3.8 12 2 UN12 2M IR16 2.1 2.6 16 3 UN16 3M IR22 3.0 4.6 12 2 UN12 2M IR22 IS22M 22 12.70 2.5 3.7 12 3 UN12 3M IR22 3.4 5.2 8 2 UN8 2M IR27 IS27M 27 15.875 2.8 4.4 18