Stainless Steel Wood screws A2 304 Torx Drive (Star) Double Countersunk Screws available in extra long lengths.
Use A4 available for marine environments. Double countersunk Heads For extra strength and sharp points to eliminate pre drilling even in most hardwoods. Ribs under head on 6mm x 140mm and above, on 8mm and 10mm Diameter. Reinforced double countersunk Head European technical approval ETA 11/0283 (Diameter 3,0 and 3,5 not component in the approval)