The 24 volts bulb for use in lamps from the Birdie family. The bulbs are produced for Ingo Maurer GmbH.
Amazon.com: Rareelectrical New Brand Light Bulb H3-24V 24 Volt 70W Halogen Clear C6 Bulb Pk22S Base Compatible With Various Applications By Part Numbers 1008 91051 H83135211 : Automotive
G4 Light Bulb 24V CLEAR 35 Watt 35MM Length 24 Volt Heavy Machinery Marine Train Cabin