I does work but needs a new battery and charger.
I saved it from the bin years ago thinking I would fix it.
Never happened, but I jumped 4v into it and it works. The knob varies the brightness, on/off.
It has a 4v 1Ah sealed lead acid battery in it. Yep its a real thing and available online.
4x4x1.5 inch
I was gonna put a lithium in it off a USB charger.
4 small screws hold it together so a pain to swap the battery, you will want to change the charging plug IMHO.
Anyway its a project for someone.
You can collect it after 6pm week days from Portfield, Chichester,