11 Watt, 12 Volt DC Compact Flourescent The Solsum/Steca (made in Germany) are 12 volt DC compact flourescent lights with a standard screw-in base. Average life is 6000 hours for the tube. Furnishes about the same light as a 60 watt incandescent bulb, but uses only 920 milliamps at 12 volts. A 7-watt is also available. Comes in cool white. This light screws into a standard household light socket. Do NOT use these lights on anything but 12 volts DC. *** Note *** On screw in (standard base) lights the CENTER is Positive (+) and the outside thread part is Negative (-). See the spec sheet (link below) for details and picture. -20°C (-4°F) to 50°C (122°F). As a consequence of the physical characteristics of the light tube, the Solsum lamp will not reach its full luminous efficiency when it is used in a low temperature environment.