Simpson Structural Screws SDW22338-R50 .22-Inch by 3-3/8-Inch with 1-9/16-Inch threaded Washer-Head Screw, 50-Pack Type T-40 Bit required with deep 6-lobe recess to prevent cam-out Low-profile heads allow hardware installation to be virtually flush Head is stamped with Simpson Strong Tie Stamp and fastener length for easy identification Bold thread design provides superior holding power and cInches fastened members together for consistent installation 1-9/16-Inch thread length and recommended installation with a low-speed 1/2-Inch drill and T-40 bit