This Harmony ZB, blue light block operates with an integral LED. It is supplied with 110V to 120V AC and uses spring terminals. It has a plastic body. It is compatible with Harmony XB4 and XB5. This light block allows fast and easy replacement and configuration of your signaling units. It is easily installed and replaced on compatible illuminated push-button or selector switch units via clip together assembly and connected with simple screw-clamp connections. It enables visual distinction of signaling units via illumination by integral LED. It protects operators from unexpected contact with live circuits thanks to its IP20 protection index. Its wide range of operating temperatures from -40°C to 70°C allows versatility in usage of product.