These Forgefix Mirror Screws are zinc plated for resistance to corrosion, and have a slotted screw head and a threaded female insert in the head and shank. They have a chrome plated dome with a threaded machine screw type male insert, and screw-in top. Often used when fixing mirrors or signage, the single threaded screws will hold firm in wall plugs. APPLICATION: Suitable for use when fixing mirrors or signage in sanitary and similar locations. Zinc coatings prevent oxidation of the protected metal to create a longer lasting finish. It does this by forming a barrier and by acting as a sacrificial anode if this barrier is damaged. Zinc oxide is a fine white dust that (in contrast to iron oxide) does not trigger a breakdown of the substrate’s surface integrity as it is formed. The zinc oxide, if left intact, can act as a barrier to further oxidation, in a way similar to the protection afforded to aluminum and stainless steels by their oxide layers. With Slotted screwdrivers it is important to ensure that the tip matches the width of the screw slot, otherwise you run the risk of damaging the screw head. Slotted screwdrivers are available with either Flared or Parallel tips. For the majority of uses the Flared tip is ideal but if the screw needs to be driven below the material surface a Parallel tip screwdriver should be used.