This is a beautifully proportioned polished gunmetal cleat. The open top is great as it can also be sued as an open fair lead. It is 4" (100mm) long, has a base width of 7/8" (22mm) and has 3/16" (5mm) holes which accept an 8g screw. The length of screw in the cleat is 7/8" (22mm) so the screws will need to be the thickness of the timber plus 22mm less a little bit so they don't penetrate the other side.