Be seen for safety, & be seen for style with this pair of LED bicycle lights that simply screw onto your wheel valves, fits both commonly used valves, presta & schrader. Just tighten & loosen to turn on & off, the lights have 5 bright LEDs that flash & change, & when cycling they create rings of bright light. Each light takes 3 x LR1130 batteries, & they come with a set of batteries to get you on the road straight away. 8cm Length Each light contains 5 LEDs Each light requires 3 x LR1130 batteries (included & replaceable) Pack of 2 lights, one for each wheel