This is a nice antique 4.0" capacity C-Clamp with the cast steel wing screw, marked "Cincinnati Tool Co. MADE IN U.S.A. ARMA STEEL." on one side of the frame, and "4" STANDARD CLAMP NO. 540 TESTED" on the other side. It is in very good usable condition with no rust, straight, not bent, good threaded rod. This type of C-Clamp is made of top quality steel and is very heavy duty. It weighs about 2 pounds.