6-18X1 5/8 Square Recess Trim Head Drywall Screw Fine Thread Black Phosphate (Pack Qty 5,000) BC-0626YQFT

For attaching wood trim to wood framing of up to 20 gage thick. The square drive variety is preferred when greater torque is required during installation AISI 1018 or equivalent steel Screws shall be quenched in liquid and then tempered by reheating to 650°F minimum