Halogen bulbs are smaller than certain other types of bulbs, which means they fit in smaller light fixtures. As for the brightness, this light bulb clocks in at 200 lumen.
From Amazon
Osram Night Breaker 200 Halogen bulb - H11-12V/60-55W - single piece
Conrad Electronic
OSRAM 64211NB200 Halogen bulb Night Breaker H11 55 W 12 V