True Power 1718 3in1 Reciprocating Saw Attachment for Power Drills Cuts copper, light steel, aluminum, PVC pipe, and wood. 3 Blades and 4mm hex key included Two fully shielded radial drive shaft bearings. Works best with 1000 RPM or higher drills. Blade teeth per inch: 5 (pruning); 6 (wood); 18 (metal). Drive shaft dim: 5/16" hex x 1-3/8"L Chuck capacity: 1/2" standard shanks; Uses most standard 1/2" shank reciprocating saw blades