Other than those specified (12V DC) are the LEDs because of upstream rectifier (D1-D4) also at AC transformers used (12V AC). The used LED driver (cl6808) allows a wide voltage range of 10-30V. Here would be a more accurate description of the technical data by greenandco desirable (10-30V; AC / DC). The warm white light color is hard to distinguish from halogen lamps. Due to the flat and small size (diameter 28mm), the product is also suitable for installation in smaller reflectors, eg with base lamps. When given power of 2.4W the LED should be able to replace a halogen lamp of 20W, but the light output is closer to a halogen lamp of 15W. Overall, a highly recommended product with good price-performance ratio.