The Electro Thermal Link (ETL)^® is a multi-purpose dual responsive fusible link / release device. The fusible link portion functions identically to that of an ordinary fusible link (ambient temperature approaching the rated temperature allows the solder alloy to melt, and the link halves to separate). Additionally, electrical actuation ( 0.2 ampere minimum trip current applied for 50 millisecond minimum duration ) starts a chemical reaction which heats the core and effects separation of the fusible link in 6 to 10 seconds at ambient temperature.

The ETL^® was designed to substantially improve life safety and minimize property damage by providing an instantaneous fusible link response and separation in the event of fire ( or at the advent of products of combustion such as smoke ) and has the additional capability to respond to any type of detector or circuit capable of supplying a short duration current impulse. The design allows for substitution or retrofit of ordinary fusible links or other actuators and release devices installed in: dampers, doors, roof hatches, towers, extinguishing systems, and inert chemical or gas release systems.

The inherent major advantage of the ETL^® over other products is dually redundant dormancy. The ETL^® is an Underwriters Laboratories^® listed space age device manufactured to exacting aerospace quality standards. It requires no maintenance, has long shelf life in an environmentally stable installation (typically 25 years demonstrated 50 years estimated) and still functions perfectly at the onset of a fire or smoke emergency.