Unlike conventional bulbs, fluorescent bulbs generate no heat. The socket on this bulb is a so-called GR10q socket.
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Osram CFL Square 16 W/827 4-PIN GR10 16 Watt Compact Fluorescent Light CFL Square 4-Pin Lamp, White
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Osram 16W 2D 4 Pin Warm White - OS816890
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Osram 16W 2D 4 Pin Warm White - OS816890
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Osram "CFL SQUARE 16 W/827 4-PIN"GR10 16 Watt Compact Fluorescent Light CFL Square 4-Pin Lamp