Below is a list of Band Heaters manufacturers from Mt. Airy, Maryland. Band heaters are thin, circular electric heaters that clamp around cylinders, pipes and nozzles to provide direct or radiant heating. Similar in construction and application to strip heaters, band heaters are used mainly in plastic and metal forming processes, particularly extrusion. Available in a virtually limitless range of widths, diameters, thicknesses, sealing capabilities and clamping options, band heaters, also known as "knuckle heaters" and "barrel heaters," provide direct heating at temperatures anywhere between 300º and 1400ºF.