I used this inside to help decorate and light up a room. The lights are much brighter than others I have tried. It is long enough to go around the room twice, which adds to the effect and really adds character to the room. Also, it plugs directly into a socket without any of those funky circular plugs. The end of the light string has a female socket in case you want to extend the lights.
Other things to note: The lights flicker vert quickly even when set to "steady-on", like some flourescent lights. The pattern changer box is not waterproof, but it comes with a water resistant bag and instructions on how to use it properly.