BEGA 2477 Lantern Installations
BEGA's 2477 luminaire was part of the range of wall luminaires with directed light. It's IP55 ingress-protection rating made it ideal for both indoor and outdoor lighting solutions. They could run a single 100W incandescent lamp, two TC-D fluorescent lamps (13W or 26W) or one 50W, 80W or 125W mercury discharge lamp. They could come in white, graphite or silver colours. The 2477 was the name for the 100W tungsten version, whereas the other lamp-types had different catalogue numbers. I've listed them below:
100W GLS - BEGA 2477
2x 13W TC-D - BEGA 2447
2x 26W TC-D - BEGA 2457
50W MBF - BEGA 2478
80W or 125W MBF - BEGA 2479
London
Near to where Park Lane meets Piccadilly is a subway system, which has at least one of the entrances lit by BEGA 2477-type luminaires mounted to the fences. I would guess that these are the fluorescent versions (so either the 2447 or 2457).