Audio and Music, BoxWave [miniBuds - headphones] Retractable In - Ear Headphone Buds for - Black/2.5mm (special 4C jack) High quality sound earphones in a portable compact design Wide frequency response: 20Hz to 20,000Hz Neodymium drivers provide 5 times more power than aluminum, cobolt, or ceramic drivers! Premium gold-plated headphone plug reduces signal loss and ensures maximum performance Re-engineered physical design specifically for audio use