48A Telephone Base Lamp

 as used in the Spilhaus Space Clock

(thank you to DonsBulbs.com, now defunct)

48A USA bulb specifications:
category:  MINIATURE
volt:  48
amp:  0.072
watt:  3.46
base:  TS3
glass:  T2
filament:  C7A
fil.res.:  667 ohm
i.lumens:  25100
cp:  2000
d.hours:  5000

ts3 base

telephone slide base number 3  (TS3 Base)

 

t2 glass

T-2 glass

 

c7afilament

C-7A filament