3 Pc Locking C Clamp Set, 6", 11", 18". 3 pc Locking C-Clamp Set 6, 11, and 18. Drop forged Jaws made of highest grade carbon steel Clamp Grip is made of high tensile carbon steel. Nickel Plated for rust resistance. Almost any item can be held with tremendous force, and will not come loose while being worked on.