The urbis zx4 is a giant street light that can have 1- 6 SON lamps up to 400w. They were mainly used on motorways and there was also a zebra version of the zx4 for lighting up zebra crossings.

M25

There are 2 urbis zx4s on the M25. I believe they both have 2 400w SON lamps and both of the lanterns work.