GRK 772691021779 12/14 by 6-Inch 3/8 Containing 1pkg Equal to 50 Screws R4 Handypack Product Description 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. From the Manufacturer 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. Features R4 Bit Table #4 uses T-10, #6 and #8 use T-15, #9, #10 and #12 all use T-25 Self-Tapping, countersinking head, W-cut thread design and Climatek coated Wood, particle board, cement fiberboard, plastic and sheet metal Multi-Purpose screw R4 ISO certified USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.