Material: steel plate iron [black] Thickness: 3MM Size: 130*170mm Countersunk screw holes and integral moldingIndustrial shelf bracket 6 inch has been upgraded to countersunk screw holes compared to other brackets, nails will not stick out after installation. The surface of the shelf bracket is completely flat, and there is no gap between the heavy duty shelf bracket and the wooden board after installation. The one-piece molding process makes the heavy-duty shelf brackets more solid. And smooth edges mean no sharp edges for you to get hurt. Easy Installation Installation steps. 1. Dig holes in the walls and boards, then install the screws 2. Tighten the screws with a screwdriver. No special skills are needed to install the wall bracket. Packing list: 2 brackets Due to the difference of different monitors, the picture may not reflect the actual color of the item. Due to manual measurement, please allow slight size error.