Special Threads, Gauges Intro UNC-UNF Code LF L(mm)(mm) D1 D2 DCON L1(mm)(mm) L2(mm) L3(mm) Type Stock YMW 1/4-28UNF CPRSU04K 73 16.5 5.91 6.00 6 9.5 12.7 15.9 01 f SP 5/16-18UNC CPRSU05O 99 22 7.23 7.38 8 12 16 20 01 f 5/16-24UNF CPRSU05M 99 22 7.42 7.53 8 12 16 20 01 f 3/8-16UNC CPRSU06P 110 27.5 8.72 8.89 10 14.3 19.1 23.8 01 f 3/8-24UNF CPRSU06M 110 27.5 8.99 9.10 10 14.3 19.1 23.8 01 f SL 7/16-14UNC CPRSU07Q 121 33 10.20 10.40 12 16.7 22.2 27.8 01 f 7/16-20UNF CPRSU07N 121 33 10.48 10.62 12 16.7 22.2 27.8 01 f 1/2-13UNC CPRSU08R 121 33 11.70 11.92 12 19.1 25.4 31.8 01 f PO 1/2-20UNF CPRSU08N 121 33 12.06 12.20 12 19.1 25.4 31.8 01 f ST ROLL CARBIDE LONG HAND TAPS EG (STI) SPECIAL THREADS, GAUGES YMW THREAD MILLS DIES CENTER DRILLS Technical info 574