1>Bearing bar pitch:30,40,60mm 2>Cross bar pitch;50,100mm 3>Plain,Serrated,I-shape ... x 7 x 4, 75 x 7 x 4, etc. 2) Bearing Bar Pitch (center to center):12.5, 15,25 ... 3/16'', 1 1/4'' x 3/16'', 1-1/2'' x 3/16'', 1'' x 1/4'', 1-1/4 ... '' x 1/4'', 1 1/2'' x 1/4''(19-w-4),(19-w-2) and so on.> 3) Cross Bar Pitch (center ... ) Australia: AS1657-1985E) Japan: JJS. Steel Grating/Floor Grating/Steel Grid