Adjustable Snap Lock Punch Punch Type Sheet Metal Punch Application Creating Locking Tabs in Light Sheet Metals Creates Hole Size 1/4 to 5/8 in Overall Length 8 in Maximum Jaw Opening 5/8 in Maximum Material Thickness Aluminum 0.035 in Jaw Opening Type Spring Return Features Compound Leverage Produces 7 to 1 Mechanical Advantage Ergonomic Redline Handles Won T Wear You Down Ideal for Crimping Gutter End Caps in Place or Creating Your Locking Tabs for Sheet Metal Duct Corners