Active Tunes i-RIDE Bicycle Stereo Speaker System Comes with the following components - Stereo mini speaker Versatile - Mounts on handlebars and bike frames. It can even be mounted upside down SAFE - No earbuds required. Tune in to your favorite music without tuning out the world around you Compatible - works with any IPOD, MP3 player, Satellite radio, good ol' portable AM/FM One size fits all - universal mounting bracket fits 21.8mm - 32mm handlebars