Sentry Industries Inc. HO495 Folding Stereo Headphones, Black Adjustable fitting stereo headphones with folding design for easy storage; with soft ear pads and padded headband Ideal for use with smartphones, cellphones, iPod, iPhone, MP3 player, tablets, PCs and laptops, DVD players, gaming and more Frequency: 20Hz - 20kHz; Impedance: 32 +/- 3 ohms; Sensitivity: 103dB +/- 3dB Drive unit (diam.in mm) - Diameter 40mm; noise isolating Tangle-free 4-feet long flat cord with 3.5mm plug