This little laser beam tail light will ensure your safety while riding in the darkness. High Quality bicycle safety laser lights. 3 red Led light modes:quick blink, slow blink and continue light.Waterproof, safer in water fog when riding in the rain Kindly Note : Do not look directly at laser lights Use for student,babystroller,jogging, walking, bicycles, car emergency, horse-riding, road emergency&camping,ETC. Battery: 2 x AAA batteries (not included)Working:9-36hours Material: ABS, Acrylic & NylonFor 20-36mm tubeInput Power: 100mWWARNING: LASER RADIATION AVOID DIRECT EYE EXPOSURE! KEEP OUT REACH OF CHILDREN!!!!