STIEF Daylight GmbH manufactures rooflight domes, continuous rooflights, smoke and heat exhaust units, dark flaps, upstands and fall-through protection at its purpose-built Leopoldshöhe plant. The company is a full member of the FVLR, the Fachverband Tageslicht und Rauchschutz, the German scheme for daylight and smoke ventilation products whose NRWG carry CE marking to EN 12101-2 and are specified to DIN 18232-2.