Rare Canon Voltage Meter Checker tester vintage 8mm camera battery case pack ?

Description

Canon
Battery Tester
Up for bids is this uber rare battery checker / volt meter from Canon. I suspect this may have been used with the Canon F-1 portable battery case which was part of the early motor drive system or perhaps a battery supply for an old 8mm or 16mm camera, but I cannot find any paperwork on it whatsoever. I have dealt with similar looking volt meters from Nikon and they were always to check the power on their portable battery packs used for the Nikon F and their 1950s rangefinders.
Ironically, I don't have anything to test the tester, so it is sold as is.
I included photos to show all sides and the tester looks to be in excellent condition. High bidder adds this rarity to their collection!
A great deal on vintage classic camera gear is waiting to be had, so get bidding today!
I'm happy to combine shipments to save you some cash!
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