This is the GEC Z9451, originally designed for 140W SO/H lanterns, and now used for 90W SOX. After a long life in Scotland, which included the fitting of a new photocell, the lantern has been retired into my collection.

The Group-B verision was the GEC Z9480 family which featured a scaled down version of the bowl.

This Group-A design was relatively short lived, with the GEC quickly introducing the V-shaped bowl of the extremely popular GEC Z9452/Z9453/Z9462/Z9453 range.