Reed's BIHSD68 is a Bi-Metal Hole Saw. It has a 4-1/4" capacity. It weighs .8 lbs. This bi-metal, variable pitch hole saw that has been designed for all machinable aluminum, cast iron, PVC, mild, tool and stainless steels, as well as nail embedded wood. It features high-speed tool steel cutting teeth for shock resistance and longer life. For use with steel, use Reed's Threadguard cutting oil, and use Bi-metal hole saws to cut cast iron dry, and PVC with water.