The OL-521 is a rear-projection video wall module conceptualised for fixed installation in industrial settings. Thanks to its modular construction, it can be set up in any desired wall size and extended later on as well. Due to its low depth of 45 cm and accessibility from the front, a more compact control room design is possible. Moreover, maintenance can take place at both the front and rear sides, eliminating the need for extra maintenance space behind the module. The image is created with LEDs which are protected from overheating by liquid cooling even when the unit is in continuous operation. Any changes in brightness and colour due to aging of the LEDs are corrected in real time.