Patented dual chamber system for clean drilling and a secure hold. Foam rubber pad for a secure hold on uneven surfaces. Flexible joint piece for moving hose to perfect position. Drilling in floors, walls and ceilings up to max. 12 mm diameter, no dust or residues. Drill sleeve made from nickel plated steel. Compatible with all standard industrial and domestic vacuum cleaners. Exception: must be deactivated on extractors with automatic filter cleaning system adapter with flexible insert.