1.Bearing bar pitches may be 12.5 to 30,32.5,40,60,80,90mm,of which 30mm is recommended.

2.Cross bar pitches may be 30 to 170mm,of which 100mm is recommended.

3.Sign of the shape of bearing bars.
F - Plain style (may be omitted in the symbol of steel grating)
S - Serrated style
I - I-section style

4.Sign of surface treatment
G - Hot galvanizing (may be omitted in the symbol of steel grating)
P - Painted,
U - untreated