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) M22×2.5 7/8-9UNC W7/8-9 STI_M18×2.5 STI_3/4-10UNC M22×2 7/8-12UN M22×1.5 7/8-14UNF STI_M20×1.5 STI_3/4-16UNF 7/8-16UN 7/8-20UNEF M22×1 7/8-28UN 7/8-32UN M22×0.5 M22×2.5 M22×2 M22×1.5 M23×2 STI_M20×2 M23×1.5 M23×1 M23×2 M23×1.5 M24×3 STI_M20×2.5 M24×2 STI_M22×1.5 M24×1.5 M24×1.25 M24×1 M24×0.5 M24×3 M24×2 M24×1.5 M25×3 1-8UNC W1-8 STI_M22×2.5 M25×2 1-12UNF STI_7/8-14UNF M25×1.5 1-16UN 1-20UNEF M25×1 1-28UN 1-32UN M25×0.5 M25×3 M25×2 M25×1.5 M26×3 STI_7/8-9UNC M26×2 M26×1.5 STI_M24×1.5 M26×1 M26×0.5 M26×3 M26×2 M26×1.5 M27×3 M27×2 STI_M24×2 M27×1.5 M27×1 * 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-23