Today more than ever all homes need surge protection from externally and internally generated transient surges. This means every electrical breaker panel in the home or structure and not just at the service entrance panel. Disconnects feeding heating and air-conditioning equipment is also recommended. Protecting all the electrical panels protects the electrical system from anything coming from the utility in addition to surges created internally from the homes electronic equipment and loads. Think of the surge suppressors like a shock absorber.. TPD surge protectors protects all the appliances, extends the life of all electrical equipment, and should be the number one priority in protecting a home.