10-9X4 6 lobe Flat w/Nibs Deep Thread Wood Screw Type 17 2/3 Thread Zinc (Pack Qty 500) BC-1064DTF17D

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