The MARSH BELLOFRAM thermometers are mostly used for industrial hot water measuring devices. They feature high levels of precision (±1%) on the entire range, and are used for hot water lines, boiler and hydronic systems, and building maintenance systems, up to 121 °C (250 °F). They have a bi-metallic element, aluminum stem and case material. They also contain 1/2" or 3/4" NPT male separable socket or 1/2" or 3/4" NPT sweatwell connection, offering easy maintenance and removal in case of sealed systems. They are highly durable and robust, guaranteeing reliability and efficiency.