Question: is gu5.3 same as mr16?
Answer: Halogen MR16 Bulbs (aka MR16 or GU5. This is a 12V lamp which requires a transformer and is quite a bit larger than the MR11. It measures 50mm across the face of the light bulb. The 5.3 in GU5. 3 means that there is a distance of 5.3mm between the two pins.