GRK R4 Multi-Purpose Screw is a versatile fastener that delivers increased productivity for hundreds of applications. Its feature-rich design provides a fast and reliable connection every time. R4 Multi-Purpose Screws have a Climatek Coating for installation in both interior and exterior conditions where exposure to moisture is intermittent and is code-approved for use in treated lumber.
GRK's R4 self-countersinking screw has a new underhead with saw-blade like cutting teeth and six self contained cutting pockets. The screw head closes the hole off with precision, leaving no damaged fibers around the head. The R4 is available in 59 sizes from #4 by 3/8-inch to #12 by 12". This multi-use screw can be used in wood, particle board, plastic, sheet metal, cement fiberboard, composite decking, wood decking and melamine. Some sizes are also available in PHEINOX stainless steel.