All The Features And Superior Performance Of The Classic Multi-Purpose Screw Manufactured From Marine Grade A4 Stainless Steel. Ideal For Coastal And Highly Corrosive Environments When Fixing To Softwoods Hardwood (Pre-Drilled) Chipboard Mdf And Plastic. Stainless Steel Must Be Used Where There Is Corrosive Environment And/Or The Base Material Has Inherent Corrosive Characteristics E.g. Green Oak.PTDTIM40025CLA4