For those with RS package (and who are flummoxed by why GM made the tail lamps LED except for the reverse lights) a lot of guys go with these. It accomplishes something similar to what I did with the reflector replacement (as far as giving some more light when going in reverse). They are not LED of course, but they are a much brighter white. The stock reverse lamps have been subject to universal scorn as to their inadequacy :-(. They are not bright at all and are a yellowy white color.
