1. Width of stair tread.
2. The flat iron for stair treads includes two kinds of: 65 x 6mm and 75 x 6mm and the size of carrier angle is L50 x 50 x 6mm.
1. Width of stair tread (W): 185, 215, 245, 275, 305.
2. Center distance between holes (A): 90, 110, 140, 170, 200.