The Catnic BSD100 lintel is the perfect go-to box lintel to specify for internal blockwork walls. It is available in several sizes to suit many different opening sizes and standard block widths. Catnic quality standards mean that the BSD 100 range comes double protected with both galvanising and powder coating, offering the lightweight strength of steel combined with durability and corrosion resistance. Solid Wall Box Lintels Key Features: 100mm Internal Solid Wall Lintel (Other Sizes Available), Heavy Duty, Available with Plaster Key, Galvanised and Corrosion Protection, Option for Built-in Insulation, Suitable for Use under Various Loading Conditions. The faces of the Catnic box lintels are ready-prepped for easy plastering, or they can be left exposed for a smart finish to face blockwork. The Catnic BSD 100 box lintels are a cost-effective, lightweight and easy-to-fit solution for internal blockwork partition wall requirements. The longest lintel in the range is 4800 mm, capable of handling loads across a 4500 mm structural opening. Lighter than an RSJ, and easier to finish with plaster and paint, it is an ideal choice for modern open-plan designs. From 750 mm up to 2100 mm the Catnic BSD 100 box lintel can take on 19 kN in loading. The longest version, at 4.8 m can deal with 27 kN, as the longer box lintels are also taller, delivering more load resistance. The SWL (safe working load) is based on the total UDL (uniform distributed load) over a maximum span with 150mm bearing at each end.