Screw Anchors are an universal fixing designed for use in all types of base material including concrete stone brick plasterboard and timber. No pre-drilling or plug required in most materials. Features / Benefits: Light duty fixing application such as signs shelf brackets and lighting and electrical fixtures. No pre-drilling required when screwing into wallboard or wood (check data sheet for additional information). When removed they leave a much smaller hole than toggles or other systems. Thread design prevents spinning and stripping Material / Coating: The screw is Zinc Plated the most common fastener of plating due to its the low cost and shinny bright silver finish. A thin layer of zinc is applied by either electroplating or mechanically. It is intended to be used internally. Whilst some people use it externally it isnt recommended if corrosion is a concern Fastener length: is generally measured from the point where the surface of the material will be when the fastener is installed to the end of the fastener. Although provided by one of our suppliers the brand supplied may be different. All material is advisory only and its use by anyone is entirely voluntary. Reliance on it for any purpose by anyone is at the sole risk of that person and Bolt and Nut Australia is not responsible for any loss claim or damages arising therefrom.