Special Thread Taps / Simple Inspection Tools CPR-S Check Pins for Bored Hole in thread form tapping (Straight Type) Spiral Fluted Taps (for blind hole) Size Code L ℓ d1 d2 ℓ1 ℓ2 ℓ3 Ds Type Stock (mm) (mm) (mm) (mm) (mm) (mm) (mm) (mm) 5/16-18UNC CPRSU05O 99 22 7.23 7.38 12 16 20 8 1 ○ 5/16-24UNF CPRSU05M 99 22 7.42 7.53 12 16 20 8 1 ○ 3/8-16UNC CPRSU06P 110 27.5 8.72 8.89 14.3 19.1 23.8 10 1 ○ Spiral Fluted Taps (for through hole) 3/8-24UNF CPRSU06M 110 27.5 8.99 9.10 14.3 19.1 23.8 10 1 ○ 7/16-14UNC CPRSU07O 121 33 10.20 10.40 16.7 22.2 27.8 12 1 ○ 7/16-20UNF CPRSU07N 121 33 10.48 10.62 16.7 22.2 27.8 12 1 ○ 1/2-13UNC CPRSU08R 121 33 11.70 11.92 19.1 25.4 31.8 12 1 ○ Spiral Pointed Taps (for through hole) 1/2-20UNF CPRSU08N 121 33 12.06 12.20 19.1 25.4 31.8 12 1 ○ Hand Taps Cemented Carbide Taps Roll Taps Special Thread Taps Simple Inspection Tools Pipe Taps Thread Mills Dies Center Drills Centering Tools JIS ST-19 ◎=Standard ○=Semi standard △=Made to order 542 For improvement, spec may change without advance notice.