Knee Defense (Poleyn)

The image shows a metal knee defense with a distinctive shape and features, by artist unknown titled "Knee Defense (Poleyn". The object is made of silver-colored metal with visible signs of wear and tear. The object has a rounded, scalloped edge and a curved shape, resembling a kidney or a shell. There are three rivets on the left side. The object appears to be a single piece with a hollow interior, and has a small opening on the left side. The background of the image is light gray.