1lb 10x4 ext screw. 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 counter sink the screw flush into wood. Compliant for treated lumber. 1 lb. box. Thread Diameter: #10, Length: 4", Pkg Size: 1 lb No. 47851: Thread Diameter: #10, Length: 3-1/2", Pkg Size: 1 lb