Reisser Cutter Countersunk Pozi Wood Screw 4 x 80mm are suitable for using with softwood, hardwood, chipboard and MDF. The screws have ribs and tucks on the head to self countersink without any surface damage. These wood screws have a deep thread with a wide and sharp point so that no pre-drilling is required. The reinforced collar reduces snapping of the screw, with the two patented slots allowing the screw to be used closer to the edge of the material without splitting.