Knockout Punch Set For Use With Tool Type Battery-Hydraulic Manual-Hydraulic Knockout Punch Component Included Punch Die and Draw Stud Material Application Aluminum Brass Copper Fiberglass Mild Steel Plastics Stainless Steel Maximum Sheet Metal Capacity-Steel 12 ga Nominal Hole Size 30.5 mm Slug Type Falls Free Punch Shape Round with Keyways Number of Pieces 5 Includes Draw Stud Yes Draw Stud Diameter 1/2 in Draw Stud Length 5 1/2 in