Ekco 4' resistor wire fluorescent fitting

I was given this light back in February 2021 by a work colleague, who informed me its been stood in a corner in his loft for around 40 years. Its likely its original to the house, but the question is, what the bloody hell is it? I know its a resistor wire fitting, and I know its made by Ekco, but after that I have no idea.

Its absolutely plastered in that lovely artex plaster, however peeling a bit back revealed a lovely duck egg blue paint beneath, as well as loads of rust, so restoration will include a total strip down and respray back to original colours.