The outer casting is made of double-walled, thick P.C.R.C. sheet re-attached with thick perforated sheet on the bottom portion, powder coated with attractive stove enamel. The distinct feature of perforated sheets is that they protect the temperature control unit from very high heat. The furnace is lagged with light-weight ceramic fiber wool insulation (instead of brick insulation). Heating elements are made of Kanthal-A1 wire in coil form, embedded on the muffle with high-grade refractory cement, and backed by high-temperature cer-wool insulation, which avoids loss of energy. This arrangement will ensure the most uniform kind of distribution of heat. The weight and size of the furnace are one quarter and 30%, respectively, as compared to brick furnaces.

A safety thermal fuse is provided to fuse when the temperature exceeds the set temperature.

A viewing cap is also provided on the door. The temperature control unit consists of a microprocessor-based digital PID temperature indicator controller fitted in front of the furnace with two indicator lamps. The apparatus is complete with one thermocouple, a silver thermal fuse, and a main lead with a power plug to work on 220/230 V or 400/440 V AC.