7-IN-1 FUNCTIONALITY: Expands, flares, and enlarges holes in copper and aluminum tubes seven sizes-6mm, 8mm, 9mm, 10mm, 12mm, 16mm, and 19mm-streamlining HVAC, refrigeration, and plumbing tasks with a single tool. ALLOY STEEL CONSTRUCTION: Forged from heat-treated alloy steel to deliver consistent performance under repeated use, resisting deformation during high-torque expansion on tubing. 6.35MM HEX SHANK COMPATIBILITY: Fits standard electric drills with a 6.35mm (1/4-inch) hex shank interface, enabling quick attachment and secure operation in workshop or field settings. PRECISE TUBE EXPANSION: Engineered for controlled, uniform expansion to prevent tube collapse and insure tight-fitting connections-perfect for professionals and serious DIY users working with lines. COMPACT and ERGONOMIC DESIGN: Measures just 117mm long with a matte black finish for simple handling and visual ; verify your sizing against the manufacturer's chart-not Amazon's-before use.