DIN rail

These products are typically made from cold rolled carbon steel sheet with a zinc-plated or chromated bright surface finish.

Although metallic, they are meant only for mechanical support and are not used as a busbar to conduct electric current, though they may provide a chassis grounding connection.

The term derives from the original specifications published by Deutsches Institut für Normung (DIN) in Germany, which have since been adopted as European (EN) and international (IEC) standards.

The EN 60715 standard specifies both a 7.5 mm (shown above) and a 15 mm deep version, which are officially designated Some manufacturers catalogues also use the terms: Top hat section / TH / TH35 (for 35mm wide) / Type O / Type Omega (Ω).

Some manufacturers (including Mean Well) use "SU" (likely stands for "standard unit", e.g. 4SU = 4 modules) [citation needed].