Circulation heaters are powerful, electric in-line heaters constructed of a screw plug or flange-mounted tubular heater assembly installed into a mating tank or vessel. Circulation Heater is designed for heating flow of liquid, oil, chemical, air or gases. It consist of a screw plug or flange-mounted tubular heater assembly installed into a mating tank or vessel. All circulation heaters are made-to-order. A wide range of heating sheath materials, wattages, vessel sizes and materials are available upon request.