Multi-size hole cutter with adjustable radius blades.  Uses: for cutting round holes in ceilings, walls and floors up to 163mm in diameter.  Cuts plasterboard, fibreboard, plywood, wood and acrylic sheets up to 23 mm depth.  Cutts aluminium, brass and metal sheets up to 1mm thick.    Comes with a transparent cowl which prevents chips/dust from flying into eyes while cutting.