Screw plug immersion heaters consist of tubular elements in a threaded hex plug. Some models are provided with a thermowell for the temperature control sensor and a variety of electrical enclosures for electrical connections. They screw directly through threaded openings in tank walls to heat liquids, viscous fluids, forced air, and gases by direct contact. A patented 360º rotatable housing is available on most models to facilitate easy conduit connections. Many models in stock.