Manufacture ISO9001:2008 Heavy load machine welded With flat even surface High strength & light structure Low Lost Serrated Galvanized Steel Grating Heavy specification:1.Bearing bar size:I (25-44)×5×3 ,(50-75)×7×4 FB19×4.5,(25-44)×(3-4.5),(50-90)×62.Section type:3.pitch of bearing bar:12.5, 15,25, 30, 30.16, 32.5, 34, 40, 41.25, 45, 50, 60, 60.32, 80, 100 4.pitch of cross bar:38, ...