GU10 bulbs are typically found in track lighting, ceiling fans, and some kinds of bath bars. The bulb itself has to fit into a relatively small space, and so the GU10 bulbs are only about 2" x 2". Developing smaller and brighter LED light bulbs is a challenge for product engineers. Heat has always been public enemy number one for LEDs. Ways and means to dissipate heat at the circuitry level have to be developed and proven over time.