2X6- 12' #1 PRESSURE TREATED L3D4S. #1 Grade. Premium Wolmanized L3 Outdoor wood. GreenSpec listed environmentally preferable wood product. Non metallic preservative.Dual mold inhibitors and built in Stabilyzer water repellent. No more corrosive to metal hardware than untreated wood,can contact alluminum without fear of accelerated corrosion. Limited Lifetime warranty against termites and decay fungi. Suited for decking and out-of-ground applications.