Introducing the "Bump" Speaker line from Aluratek. Simply connect with MP3 players, Mobile Phones, Portable CD Players, iPod and iPhone, eBook Readers, Laptops and Netbooks and other audio devices with 3.5mm Auxiliary audio output for superior sound quality.
In the from beginning, I thought need to buy two to enough let all the students in the class can hear it. But, the one speaker sound already full filled the whole classroom, and quality is great.