The GRAFT high-bay LED luminaire has been developed jointly by Zumtobel and ARUP. GRAFT provides high luminous flux levels of 28,000 lumens for lighting tasks in industrial areas; innovative lens technology allows for high-precision light control. The luminaire features square and narrow-beam lighting characteristics to perform a variety of lighting tasks; the lighting solution's uniformity and efficiency are improved as the luminous fields do not overlap. A special design feature, the rib structure, ensures the cooling and cleaning of the luminaire on account of the airflow, which significantly increases the LED's service life.