... well cover, suspended ceiling, ventilation and penetration of light, etc High strength: The strength and the toughness are much ... 1''x1/8'', 1 1/4''x1/8'', 11/2''x1/8''etc 2Bearing Bar Pitch12.5, 15, 20, 23.85 ... , 15-w-4, 11-w-4, 19-w-2, 15-w-2 etc. 3Twisted Cross Bar Pitch38.1, 50, 60, 76 ... , 80, 100, 101.6, 120mm, 2'' & 4'' etc 4Material GradeASTM A36, A1011, A569, Q235, S275JR, SS304, Mild ...