The conventional energy saving bulbs were designed for inside use & normal room temperatures. Muller Licht cold resistant energy saving bulbs have been especially designed for use outside & for rooms with low temperatures like garages, cellars & cool rooms. The bulbs are cold resistant up to – 20° C & even shine brightly at low temperatures. Amalgam / cold resistant up to -20° C Specially designed for outside use Shines brightly, not dependant on temperature Average life 10, 000 hours Start up quickly Light colour 2700 K, warm white Not dimmable! Average 10, 000 switching cycles 15 W is the same as &8805;54 W light equivalence 20 W is the same as &8805; 77 W light equivalence