Device carrier made of galvanized, profiled steel sheet with a surface coated in polyester resin. Tool-free attachment with integrated side lever locks for quick insertion into the support rail. LED unit in housing length for a visually continuous light strip, variably positionable in the support rail. Diffuser optics with direct/indirect light distribution using an opal plastic diffuser made of PMMA. With internal longitudinal prisms, it creates a uniform, homogeneous appearance with ceiling illumination and a UGR (4H/8H) of 25.2. Heat-resistant cables including a connection cable of 1 m for variable device carrier positioning in the light strip and a 3-pole or, in dimmable models, a 5-pole quick-mount plug part with free phase selection.