Weldsale KNEE. This is an Angle Bracket. It measures 4 inches wide x 10 inches deep x 12 inches overall height. It is similar to a typical machinist angle, but specially designed for you to use on your Platen. This will provide both a right angle surface, and – with the typical Weldsale square hole on top – provide elevated clamping, using a typical weldsale clamp. So. you can clamp your workpiece in the vertical axis and/or gain an additional 12 inches of clamping elevation. This will work on both new and used Platens. This comes with two bolts, nuts, and washers for bolting down to Platen.