A must have for hanging doors, this spring loaded corner chisel is more efficient than a hand chisel, and works quickly to ensure that corners are perfectly square. Compact enough to carry in your pocket, with a 3/8-inch cutter edge, this handy tool creates a 90 degree square corner when simply placed on any corner and tapped with a hammer. And because the PORTER-CABLE 42234 corner chisel self aligns, accuracy is never an issue; you get the right fit every time with minimal maneuvering.