Sentry Industries Inc. HM371 MicBuds Metal Stereo Ear Buds With Built-In Mic, Black Ideal for use with smartphone, cell phone, MP3, iPod, iPhone, iPad, tablets and more Listen to music and talk to friends with two-line built-in click control Omni microphone Drive unit (diam.in mm) - Diameter 8mm; Frequency: 20Hz - 20KHz; Impedance: 16 ohms Acoustic sub-woofer chamber 4-feet long metal finish cord with 3.5mm plug