Overall Thread Thread+Neck Shank Shank Size of Length of length length length length dia. square square L ℓ ℓn ℓs Ds K ℓk SP (for blind hole) Spiral Fluted Taps Spiral Fluted Taps Specification (for through hole) Spiral Fluted Taps E 1 1/8U ~ Recommended Tapping Speed depending on Materials (for through hole) Spiral Pointed Taps Medium carbon steels 5〜10 For icon explanation, refer to P.50 TYPE:1 TYPE:2 Hand Taps Carbide Taps Cemented TYPE:3 TYPE:4 Roll Taps Segment:1C Simple Inspection Tools Pipe Taps Size Class Code Chamfer L ℓ ℓn ℓs Ds K ℓk No. of Type (inch) (inch) (inch) (inch) (inch) (inch) (inch) flutes For Unified Threads GH1 SSUN2E1NEB No.2-56UNC 2.5P 1.772 0.314 - 1.161 0.141 0.11 0.187 2 1 GH2 SSUN2E2NEB GH1 SSUN2D1NEB Thread Mills No.2-64UNF 2.5P 1.772 0.314 - 1.161 0.141 0.11 0.187 2 1 GH2 SSUN2D2NEB GH1 SSUN3F1NEB No.3-48UNC 2.5P 2.205 0.354 0.669 1.28 0.141 0.11 0.187 2 2 GH2 SSUN3F2NEB GH1 SSUN3E1NEB No.3-56UNF 2.5P 2.205 0.354 0.669 1.28 0.141 0.11 0.187 2 2 Dies GH2 SSUN3E2NEB GH1 SSUN4H1NEB No.4-40UNC 2.5P 2.205 0.354 0.709 1.28 0.141 0.11 0.187 2 2 GH2 SSUN4H2NEB GH1 SSUN4F1NEB No.4-48UNF 2.5P 2.205 0.354 0.709 1.28 0.141 0.11 0.187 2 2 Center Drills GH2 SSUN4F2NEB GH1 SSUN5H1NEB No.5-40UNC 2.5P 2.205 0.433 0.768 1.358 0.141 0.11 0.187 2 2 GH2 SSUN5H2NEB GH1 SSUN5G1NEB No.5-44UNF 2.5P 2.205 0.433 0.768 1.358 0.141 0.11 0.187 2 2 GH2 SSUN5G2NEB Centering Tools GH1 SSUN6J1NEB No.6-32UNC GH2 SSUN6J2NEB 2.5P 2.205 0.433 0.768 1.358 0.141 0.11 0.187 3 2 GH3 SSUN6J3NEB ANSI SP-2 189