WOWee One Power Bass Portable Speaker for iPad, iPhone, MP3 Players, Laptops, Mobile Phones, and Personal Game Systems (Black with Silver) Patented Gel Audio Technology Big Sound - Turns any surface into sound to produce deep bass in a palm-sized device. Portable - Pocket-sized for on-the-go sound. Up to 20 hours of playtime per charge with internal lithium ion battery. Compatible - For all iPod , iPad , mp3, mobile phone, computers and gaming devices using a standard 3.5mm headphone jack. Easy to Use - Just plug and play. Works on everyday surfaces like walls, windows, tables, desks, coolers, etc.