Constructed from tempered, high carbon tool steel, the Large Square Cutter Set includes 4 punches in the following sizes: 10, 15, 20, and 27 mm. Lever style opener is used to spread the die plates apart and to apply clamping pressure to the metal being cut. For use with soft metals 22 gauge (0.64 mm) and thinner. Block dimensions are 3" x 3 1/4" x 1 1/4" high (without the cutters and handle). Works best when positioned over a rubber bench block (see related products below).