This is a corner shield. It comes in a clear polycarbonate construction. Each corner is 3/4 in. x 3/4 in. x 48 in. in length with a pre-drilled holes. To install make sure the corner you are trying to protect has been cleared of obstructions. The thickness is 0.045 in. of each wall of the corner protector. Typically these corners are used to protect or repair 90 degree corners from chipped paint, torn wallpaper or fingerprints. All the necessary mounting hardware is included for a quick and easy installation. A hammer or tack hammer will be required for installation.