A: The grid clip is made of plastic and the S-hook is made of metal.
A: They are small plastic white clips maybe about 1 square inch (give or take). The plastic is not forgiving and will break easily, but the S hook that comes with it is metal and sturdy. We are using these to hang lightweight sneeze barriers and they are working out just fine. The plastic grip adheres to the metal ceiling tile frame securely so they don't move.
A: The main body is plastic with a small metal hook. It is very small, less than an inch square, and the S hook is also small, about an inch long.