Use energy-efficient light bulbs if you're looking to cut as much energy costs as possible. The socket on this bulb is a so-called G24q-2 socket.
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Osram Dulux DE 18w / 830 Energy Saving 4-PIN lamp - Warm White - G24q-2 D/E
LED Bulbs
Osram 18W Dulux CFL DE 4 PIN Warm White - OS327211
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