General description The AlwaysH Square Hole Drill Adapter is a heavy-duty mounting bracket designed for quickly installing or disassembling square hole drills on both table and hand drills. This adapter is compatible with drills that have clamping diameters ranging from 38 to 55 mm (1.5 to 2.2 inches). Technical specifications Clamping diameter: 38-55 mm (1.5-2.2 inches) Compatibility and accessories Compatible with bench and hand drills Note: The product does not include square drills or electric drills Installation Easy to install and remove Can be quickly installed or removed by the user