MR16 and G4 bulbs work with a 12v transformer. GU10s work without a transformer and at 220V, which means they go directly to the domestic electricity grid. We have dichroic GU10 dimmable (dimmable) to dim or intensify the light at will. These LED bulbs are highly recommended if we want to change the old incandescent bulbs by LED technology. In FactorLED we offer different models of GU10 to the consumer's liking and a wide variety of powers .. and you already know how to place them in the type of bull's-eye luminaire. Discover them in our store FactorLED!