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) M16×2 M16×1.5 M16×1.25 M16×1 M16×0.75 M17×1.5 STI_M14×2 STI_9/16-18UNF M17×1 M17×0.5 M17×1.5 M18×2.5 M18×2 STI_9/16-12UNC M18×1.5 STI_M16×1.5 M18×1.25 STI_5/8-18UNF M18×1 STI_M16×1 M18×0.75 M18×0.5 M18×2.5 M18×2 M18×1.5 M18×1.25 M19×2.5 3/4-10UNC W3/4-10 STI_5/8-11UNC M19×2 3/4-12UN STI_M16×2 M19×1.5 3/4-16UNF 3/4-20UNEF M19×1 3/4-28UN 3/4-32UN M19×2.5 M19×2 M19×1.5 M20×2.5 M20×2 M20×1.5 STI_M18×1.5 M20×1.25 M20×1 M20×2.5 M20×2 M20×1.5 M21×1.5 M21×1 M21×1.5 * 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-21