A cartridge heater is essentially a tube-shaped, lightweight, heavy duty, high power electric Joule heating device used in the electrical heating industry, generally custom made for a particular wattage density, depending upon its intended use. Generally these are used as portable heaters and can be connected to a standard electrical outlet through a cigarette lighter or similar plug. The heaters are available in a variety of wattage ranges, from one hundred watts up to one thousand watts. Depending upon what you need the heater to do, they may be suitable.
Electric cartridge heater come in all shapes and sizes. Some are specifically designed for outdoor applications, while others are ideal for indoor use. Many are built with extra large coils for higher wattage. Many are powered by a single twelve-volt outlet and can operate even when electrical power is out. Others can be placed under an unheated building or a floor or wall of water, using a water pump, water heater or other system.
These are also known as reciprocating heaters and are used by professionals in electric heating. They are ideal for heating an area that is enclosed, like a room, but do not have air ventilation to vent the hot air out. They do not have a fan, so do not require a ventilation system, which is very advantageous, especially in hot climates. Also, a reciprocating heater uses up less electricity and does not generate fumes. These heaters are generally made of aluminum alloy or stainless steel, but nickel, bronze, iron and copper all are used as well.