When it comes to infrared emitters, the choice of different frequency depends on several characteristics like material absorbency, heating necessities and speed and type of application. There is a gold reflector on the back side of the twin-tube emitter which amplifies the radiation yield and enhances directionality.
The use of the twin-tube of quartz crystal makes it a more stable element compared to other normal single tube. The ends are made in a way to ensure minimal radiation loss. Infrared in twin-tube version can be manufactured with one single connection end and simplifying installation.