Klein Tools 86526 HVAC Tool V Notcher for Ductwork and Sheet Metal,

Cuts 30-degree V shapes in sheet metal quickly and easily to make corners Drop-forged, high impact steel jaw with 13/16-Inch (2.1 cm) maximum throat depth Jaw's hook design allows easy notching of corners and take-off tabs without slippage For up to 24 gauge steel and 26 gauge stainless steel Comfortable, contoured grips cover hardened steel handles