Quote from Roller Girl Gang: 
The Luminous Wheels are the brightest we have ever tried and our favourite. We love these wheels, because during the day, you have a bright, pretty wheel, and during the evening they additionally flash. We love to skate indoors and outdoors, and while the mid-hardness is not specialist to either indoor or outdoor, it is a perfect leisure wheel. (By specialist, I mean that you probably wouldn't skate a long distance outdoors in these wheels, where a softer wheel would provide more comfort, nor are they designed for high speed spinning and super precise jumps and landings, where a much harder wheel is required.)

Please note these wheels are sold in units and not packs of 4 - but we would recommend taking more than one as they can get very lonely.

Softer is smooth and has more grip and harder wheels are more forgiving and controllable when learning new tricks or Jam techniques. If you are skating recreational outdoors, we would recommend the bigger and softer version of these wheels