GRK’s R4™ self-countersinking screw has an under head with saw-blade like patented cutting teeth and six self-contained cutting pockets. Together these features act like a circular saw blade, transporting the "drill dust" away from the edge of the screw hole while cutting a perfectly clean hole into even the most brittle materials without cracking any surface treatment. This design further enhances the R4™’s versatility by allowing the fastener to be installed without countersinking into even the hardest woods. The screw head closes the hole off with precision, leaving no damaged fibers around the head.
- Pheinox R4 #9 & #10 Screws require a T-25 bit
||GRK Pheinox R4 Stainless Steel Screw quantities vary by selection