Skque Cycling Bike Motor Car Wheel Valve Cap Fireflys Lights, Blue High quality bicycle wheel valve caps fireflys lights. The light is Set on the bicycle valve, it will be on and flash when the wheel runs. Directly install onto the standard American or British valves. The light will be off when the vehicle stops,on when it runs,and flash when you are driving at night. Enhances safety by increasing visibility at night and during bad weather conditions.