The MGN 12 C is a narrow-width miniature linear guide block from the MGN series, designed for compact and precise linear motion applications. It runs on a 12 mm wide rail, with the carriage block approximately 27 mm wide and an assembly height of about 13 mm. Its light weight, roughly 0.03–0.034 kg, makes it ideal for small machinery and devices where space is limited.

The block uses a Gothic-arch contact geometry for its ball bearings, providing good stiffness and rigidity and allowing it to withstand loads from multiple directions, including moment loads, despite its small footprint. The balls are retained in a cage, keeping them captive even if the block is removed from the rail, which simplifies assembly and maintenance.

Because of its compact size, low weight, and smooth low-friction motion, the MGN 12 C is well-suited for applications such as 3D printers, small CNC machines, robotics, measuring instruments, and other miniature automated systems where precision and space efficiency are more important than heavy-load capacity.