Forgefix wood screw slotted csk solid brass forgefix csk18br these forgefix traditional slotted single thread wood screws have countersunk heads and can be used in many internal and external applications they have a solid brass construction to avoid corrosion used for both decorative and in applications where the screw may come in to contact with the elements avoiding corrosion can be used with all manner of wall plugs slotted screw driver required with slotted screwdrivers it is import