Marine Grade Stainless Steel A4 316 Torx Double Countersunk Screws available in extra long lengths. Torx TX25.

Use A4 for fixing in coastal regions, it is also the best option for Green Oak and other woods with a high level of tannin.

5.0mm x 20mm Full Thread	5.0mm x 25mm 18mm Part Thread	5.0mm x 30mm 20mm Part Thread
5.0mm x 35mm 24mm Part Thread	5,0mm x 40mm 24mm Part Thread	5.0mm x 45mm 30mm Part Thread
5.0mm x 50mm 30mm Part Thread	5.0mm x 55mm 36mm Part Thread	5.0mm x 60mm 36mm Part Thread
5.0mm x 70mm 42mm Part Thread	5.0mm x 80mm 48mm Part Thread	5.0mm x 90mm 54mm Part Thread
5.0mm x 100mm 60mm Part Thread	5.0mm x 120mm 70mm Part Thread

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. A4 available for marine environments. 
European technical approval
ETA 11/0283 (Diameter 3,0 and 3,5 not component in the approval)

3.0mm Diameter	3.5mm Diameter	4.0mm Diameter
4.5mm Diameter	5.0mm Diameter	6.0mm Diameter
8.0mm Diameter	10.0mm Diameter

Stainles Steel A4 316 marine grade wood screws with a double countersunk reinforced head.

Available with plain head and sharp point or Ribbed head and cutting tip.