Beamlight  Reiche & Vogel

R&V 1000W Beamlight
(from GearSource Europe)

Low voltage parallel beam lantern
The most commonly used model was the 24V 500W (using Crown-Silvered lamp 570B with E40 base)
Beam angle: 14-20 degrees

R&V also made 250W and 1000W versions, all at 24V. 

German: Niedervolt Spiegelscheinwerfer