They are sometimes used, however aren't really used since metal halide and high pressure sodium are much better. Get one of those or flourescent (flourescent doesn't perform as well.)
mountainman Reviewed by mountainman on . Is this a good source of light? Im not sure if its any good. all i know is its used for tanning indoors, old school. Mercury Vapor lamp.. :confused: http://img178.imageshack.us/img178/8276/light8pw.jpg Rating: 5