ForgeFix Machine Screw Pozi Pan Head ZP - ForgeFix 25MSPH520, These Forgefix Pozidriv Machine Screws are designed for use with nuts or pre-tapped holes. They are Zinc plated for increased corrosion resistance. Their Pan Head with a flat under head surface makes the screws ideal to lay flat on sheet material of all types, thus reducing deformation. Ideal for use in many DIY, ironmongery, electrical and plumbing applications. 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 substrates 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 aluminium and stainless steels by their oxide layers. The Pozidriv screw is similar in appearance to the classic