T5 recessed fittings are commonly known as LBR (low brightness louvre) grilles or PC prismatic diffusers depending on the type of cover. They are used to replace T8/T12 recessed fittings, which would be removed entirely from the ceiling and a new T5 fixture put in its place.
Recessed fittings are only used where the application allows for a partitioned ceiling with removable panels. T5 recessed fittings use T5 High-Efficiency (HE) fluorescent tubes which offer high rates of energy savings. Similarly LBR and Diffuser fittings can be made to accommodate surface-mountable applications.
Application: Predominantly indoor areas where a ceiling is present. Usually seen in offices or passageways.