... ' requirementsFor example:1) Bearing bar pitches may be 12.5, 15 to 30, 40, 60, 80 and 90mm; of which 30and ... '', 1 1/2''x1/8'' etc 2Bearing Bar Pitch12.5, 15, 20, 23.85, 25, 30, 30.16, 30.3, 32 ... , 80mm etcUS standard: 19-w-4, 15-w-4, 11-w-4, 19-w-2, 15-w-2 etc. 3Twisted Cross Bar ... -1985,Germany: DIN24537-1-2006, Japan:JIS galvanized steel grating ladder (factory)