These Forgefix General Purpose Pozi Screws with Countersunk heads are zinc plated for increased durability. They are an extremely popular general purpose screw, & suitable for use in & with many materials. Application: ideal to be used in many ironmongery, electrical & plumbing applications. Can be used with various screw cover caps. Zinc coatings prevent oxidation of the protected metal to create a longer lasting finish. It does this by forming a barrier & by acting as a sacrificial a