Extension cords; signal line telephone wire; [ electrical inductor; ] electric light dimmers; switchboards; electric light on/off controllers; electronic servo-motor controllers; electric power stabilizers; electric power supply; electric buzzers; electric automatic door controllers; photoelectric sensors; programmable electronic logic controller units for use with lights and switches; electromagnetic lock switches; electric touch switches; electric light controllers; electric infrared sensors; electric ultrasonic sensors; acoustic membrane switches; electric outlet covers