These are so much fun! The Monster Bluetooth Sound-Reactive LED Car Lights are easy to use and add that pop of color you’re looking for! They simply stick to any interior hard surface and plug into the DC outlet. You download the app on your phone to change colors and use the cool reactive music mode! Every time I pick up my 4yr old Niece, we have to have at least one car dance party! I couldn’t be happier with The Monster Bluetooth Sound-Reactive LED Car Lights and I would highly recommend them to everyone!!!