Power Pro screws. For exterior applications. Bronze ceramic coating. Approximately 1000 hours salt spray resistance. Made of hardened steel. Star drive provides twice the drive torque of Phillips or square drive. Driver bit in every package. Type 17 drill tip drives in wood without pre drilling. Cross cut thread prevents wood from splitting and reduces friction. Flat head with countersinking nibs under the head will countersink the screw flush into wood. Compliant for treated lumber. Bulk.