PRAD SYSTEM PRAD system Solution tool PRAD system Specification corresponding with standard blanks(for Japanese market) Material Symbols HSS:○ HSS-Co:● HSS-P:◎ Main size designation and specification ① ② ③ ④ ⑤ STI ⑥ STI metric unified whitworth sewing screw (metric) (unified) - 1/4-20UNC W1/4-20 SM1/4-24 1/4-28UNF SM1/4-28 SM1/4-40 M7×1 STI_№12-24UNC STI_№12-28UNF M7×0.75 STI_M6×0.75 M7×0.5 M7×1 M7×0.75 M8×1.25 5/16-18UNC W5/16-18 5/16-20UN STI_1/4-20UNC M8×1 5/16-24UNF STI_M6×1 5/16-28UN STI_1/4-28UNF M8×0.75 5/16-32UNEF M8×0.5 M8×1.25 M8×1 M8×0.75 M9×1.25 M9×1 M9×0.75 M9×0.5 M9×1.25 M9×1 M9×0.75 M10×1.5 3/8-16UNC W3/8-16 STI_5/16-18UNC M10×1.25 3/8-20UN STI_M8×1.25 M10×1 3/8-24UNF STI_M8×1 STI_5/16-24UNF 3/8-28UN M10×0.75 3/8-32UNEF M10×0.5 M10×1.5 M10×1.25 M10×1 M11×1.5 M11×1.25 STI_M9×1.25 M11×1 STI_M9×1 STI_3/8-24UNF M11×0.75 M11×0.5 M11×1.5 M11×1.25 M11×1 M12×1.75 7/16-14UNC W7/16-14 M12×1.5 7/16-16UN STI_M10×1.5 STI_3/8-16UNC M12×1.25 7/16-20UNF STI_M10×1.25 M12×1 7/16-28UNEF STI_M10×1 M12×0.75 7/16-32UN M12×0.5 * Corresponding pitches meet with the pitches of other kinds. * Concerning Hand of threads, both right and left are applicable in the same blank. * Concerning the kind of taps, SP, PO, HT, ROLL are applicable in the same blank. * Concerning applicable thread limits, maximum applicable thread limits for metric coase threads are listed. * is a blank for Z-PRO. PRAD-17