Compact, lightweight and reliable modular units designed for space constrained installations. Function and value: scalable expansion for control panels, instrumentation, or network equipment; supports reliable operation while saving rack space. Compatibility and mounting: mounts on standard rails or multi slot racks; verify the model number before to ensure correct fit. Size and build: compact footprint with a robust housing for durable, long term use; measurement tolerance is 13 mm due to manual measurement. Performance: designed for stable operation in typical industrial or lab environments. Use scenarios: 1) Automation control panel on a production line adding extra I/O or functions. 2) Lab instrument rack for modular testing and data logging. 3) Small cabinet in data center or telecom rack for scalable, space efficient expansion.