Galvanised Batten Screws are popular for fastening heavy timbers where corrosion resistance is required, such as external environments.
The self embedding countersunk head sits flush with the timber board. For ease of installation and a cleaner finish you may want to consider a pre-drilling and countersinking tool such as the SMART-BIT.
Type 17 point is designed for driving and carving through timber, both hardwood and softwood.
Features an internal 5mm hex drive and free drive bit.