Goldscrew Yellow zinc-plated Carbon Steel Woodscrews (Dia)5mm (L)50mm Pack of 200. This pack of Prodrive drive recess countersunk flat head wood screws are constructed from a durable case & are through hardened. They are 50mm in length & come partially threaded on longer screws. They have coarse thread & come wax coated for lubrication. They're ideal for a range of DIY applications.