Electronic Vacuum Regulator Valve

regulator valve
The main steam control of a locomotive. Various types of valve and various locations for it were to be seen during the history of the locomotive but it was normally at the top of the boiler where the steam was hottest and usually in a dome.

electronic
(of a device) Having or operating with the aid of many small components, esp. microchips and transistors, that control and direct an electric current
Of or relating to electronics
Electronic were an alternative dance group formed by New Order singer and guitarist Bernard Sumner and ex-Smiths guitarist Johnny Marr.
(of music) Produced by electronic instruments
of or relating to electronics; concerned with or using devices that operate on principles governing the behavior of electrons; "electronic devices"
Electronic is the self-titled debut album by British supergroup Electronic, formed by Bernard Sumner and Johnny Marr. It was first released in May 1991 (see 1991 in music) on the Factory label, and reissued in remastered form in 1994 by Parlophone after Factory collapsed.

vacuum
A space entirely devoid of matter
A gap left by the loss, death, or departure of someone or something formerly playing a significant part in a situation or activity
void: an empty area or space; "the huge desert voids"; "the emptiness of outer space"; "without their support he'll be ruling in a vacuum"
A space or container from which the air has been completely or partly removed
clean with a vacuum cleaner; "vacuum the carpets"
the absence of matter