A component which converts available alternating current or direct current electrical power into a form required to operate another component or set. the item may consist of a combination of an invertor, vibrator; vibrator, interrupter; vibrator, self-rectifying; invertor, power, static; with a transformer and rectifier(s) employing electron tubes, semiconductor diode or metallic (dry disc) type components, or the synchronized secondary contact(s) of a vibrator, self-rectifying; or may consist of electron tubes, semiconductor diode or metallic (dry disc) type rectifiers and capacitors in transformerless (alternating current-direct current type) circuits which may be of the voltage-multiplier type. the item may incorporate a filter, direct current power and provisions for regulation of input and/or output voltage. the item may have special input, output, control or other facilities for applications in specialized environments such as medical, dental or other operations. excludes battery chargers and rotating machinery types of items, such as motor generators and dynamotors.