The B50M system is an exclusive high-quality system designed to cover large areas with different types of fabric. Unlike the B50 system, this variant is equipped with metal sides that allow the use of electric drives from most leading suppliers. The B50M system cannot be controlled by a ball chain.

It has a two-part aluminium cassette (the rear section can be used on its own as a mounting rail and, when combined with the front section, forms a square profile cassette). The system is assembled by attaching the cassette with clips.