The Sylvania Lynx-QE square CFL bulbs are very energy-efficient and the flat & thin design ensures an easy installation in fixtures. In addition, the square shape allows an even light distribution without any shadows. Sylvania Lynx-QE energy saving bulbs possess a 4-pin plug in system and are used in combination with an electronic ballast. The long average lifespan of 11.000 burning hours make sure that Sylvania Lynx CFL bulbs do not need to be replaced often. As a result, there is also less lamp waste, which is good for the environment!