Clippard valve for Ghostbusters proton pack

Clippard R-701 valve as used on the proton packs and throwers.
This and the R331 are both used on the packs & throwers in various configurations:

(Info from Gbfans.com)

Sony Hero Lobby
R-701 on pack
R-331 on gun

Minnesota/Archive "Venkman" GB1 Pack
R-331 on pack
R-701 on gun

England GB1 "Stantz" Pack in private collection
R-701 on pack
R-701 on gun

PIH GB1 "Spengler" GB1 pack
R-701 on pack
R-701 on gun

Sony Lobby GB2 semi hero
R-701 on pack
R-701 on gun

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