510mm x 480mm x 255mm Balanced Flue Terminal Guard - BS 5440 Part 1 Zinc Plated Square This large square zinc-plated balanced flue terminal guard is designed for low-level installations. One thing to keep in mind is that the BS 5440 Part 1 guidelines actually say you should fit a terminal guard if you're going to have a balanced flue terminal installed at low level - to stop it getting knocked and to stop people getting too close to the hot terminal. This one measures 510mm high x 480mm wide x 255mm deep and has a zinc plating for protecting against corrosion on the outside. If you're used to using the 11 round terminal guard for smaller circular balanced flue terminals, this square version is perfect for wider or rectangular ones. The BS 5440 Part 1 committee are pretty keen on recommending that you fit a terminal guard when the bottom of a bal