AC 12V / DC 12V LED Spotlight: It is better to use an LED transformer. If you want to connect a halogen transformer, please make sure that the full power of the LED bulbs reaches the lowest wattage of your transformers, otherwise they may flicker strongly. MR 16 / GU5.3 / GX5.3 5W LED replaces 50W halogen, 450Lumen, Voltage AC 12V / DC 12V (AC12V or DC12V LED transformer required), Non-dimmable, Dimensions (ØxL): 50 x 39 mm Durable GU5.3 reflector: with CE, EMC and RoHS certification. No flickering, no UV or IR radiation. Made of high-quality materials with excellent heat dissipation 12V 50W Cool White Floodlight: High reflective index Ra80 with super 30 x 5730 SMD, uniform illumination. Energy efficiency class A +, long lifespan, energy saving up to 90% Attention!! Please make sure your transformers are LED or halogen transformers. If they are halogen transformers, they may cause MR16 LED bulbs to flicker. Consider replacing them with an LED transformer. Save Your Electricity Bill 5W