With thanks to James for identifying and providing the following information on these fittings. These batten-type lights were manufactured by AEI for British Rail, with other manufacturers such as GEC producing them before their own weatherpacks were used for the same role. The fixtures were for two 5ft fluorescent tubes, with the bowls being held on by deutz fasteners or quarter-inch whitworth bolts.

Stafford

These stunning survivors exist within the heart of Stafford Station, with twelve in total installed on a section of the ceiling over platforms 4 and 5. The current building of Stafford Station was constructed in 1962 - likely the same year that these fluorescent lights were installed.

The bowls appear to be made of some-kind of acrylic material, but the opal appearance was likely an original feature of the lights. There is no evidence that these had the station name on them originally, but some versions could I believe.

One of the twelve fluorescent canopy lights is missing its cover (and likely a reflective tray as well) giving an idea as to the internal construction. The outline of two removed ballasts are visible despite all of the diesel fumes covering the underside of the lanterns in an inky coating.

A terminal is visible at one end of the lantern.

The other ones on this side of the tracks still retain their bowls.

There appears to be a cavity above the lights (roughly the same size as them) which is consistent with the idea that these were installed in 1962, and are original to the building. A number of similar sized holes can be found around the station, notably on platform 1 in the concrete struts that hold the canopy up, and on platform 4 above the vending machines. This indicates that the remaining twelve may not have been the only lanterns of their kind in this station, only having survived as the logistical difficulty of removing twelve lights over an active railway line wasn't worth it - especially when they weren't a risk to anyone below and could simply be disconnected.

The stairs provide a good elevated view of these lights:

Below are some of the modern replacement bulkheads, which are made by Thorlux.

There appears to be stickers on a few of the lanterns' bowls, but these have long-since been coated to unreadability by train diesel and general muck.

This excellent angle provides insight as to how exactly the lanterns fix to the ceiling. Three metal rods are present in the image below, and I'd presume one of these carries the supply cable.

This was not the only time I'd visited these fluorescent lanterns. below are some images taken during my original discovery of them - I almost made myself miss my connecting train willingly to take photos - but I did make it!