BLR121 battery for AVO

[AlanBeckett]

It must date from after 1978 and before 1994 because that's period I worked for the place where I liberated it from.
Although it says AVO on it I'm pretty sure it came from RS.
Anybody got an ancient Catalogue?

There's this - http://www.richardsradios.co.uk/vc1.html

Alan