Honeywell's 2455RC series is a single pole, single throw, snap-acting, non-adjustable thermostat which may be used in applications such as industrial and electrical equipment. A temperature-sensitive bimetal disc, electrically and thermally isolated from the switch, is used to actuate the normally closed contacts. Due to the small size of this unit and the inherently low mass of the bimetal snap-action disc, response of this thermostat to temperature changes is extremely rapid, compared to other commercially available thermostatic devices.