The MCBH-00 Contact Block Holder is: Maintained/Momentary - Front mounting - 3 This Contact Block Holder is part of ABB's modular plastic range, the most versatile range with a high level of flexibility and market-leading electrical ratings. Engineered for total reliability, longer lifetime and highest mechanical durability. Self-cleaning contacts ensure reliable operation without the need for maintenance, increasing uptime. A high degree of protection guarantees reliability in extreme environments. The innovative design simplifies the entire process, from selection to easy and quick, tool-free installation. The perfect solution for every application.