Opening spring for cutting iron, copper, or aluminum sheet metal up to a maximum thickness of 1.2 mm, and plastic up to a maximum thickness of 2.0 mm. Materials are cut without deformation, resulting in clean cut edges with no trimming activities needed. Features a chip breaker. Cutting width: 2.7 mm. Capacity includes half-moon, square millimeters, square drive, square, step-like square, triangular, and clamping widths for hexagon, round, and square shapes.