9X2 1/2 6 lobe Flat w/Nibs Deep Thread Wood Screw Type 17 2/3 Thread Black Oxide (Pack Qty 2,200) BC-0940DTF17B

The deeper thread design offers greater resistance to pull-out forces. The six-lobe recess transmits drive torque with less required downward pressure C1022 case-hardened steel Rockwell C 45 minimim