Even light bulbs have an energy rating, and this one is A-rated. On this light bulb you'll find a G13 socket.
From Amazon
Osram. Fluorescent Tube T8 18W 865. 598 X 26mm.
LED Bulbs
Osram 18W T8 Fluorescent Tube 600mm 2FT Daylight - 4050300517773
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