The C-rail bearing unit 8 K is a pre-machined bearing unit for simple assembly of compact C-rail systems. The K variant is equipped with plastic rollers on plain bearings that run directly in the rail profile. This variant 8 K can be loaded with Fmax = 250 N and meets simple guiding requirements. In general, C-rail systems are variable and safe track roller guides and are designed in particular for the construction of lifting and sliding doors.