Hamilton Electronics HA7 SchoolMate Deluxe Stereo Headphone with 3.5mm Plug<div style="text-align: left;"><strong>[Product Information]</strong><ul><li id="replacementPartsFitmentBullet" class="aok-hidden" data-doesntfitmessage="We're not sure this item fits your " data-fitsmessage="This fits your "><span class="a-list-item"><span id="replacementPartsFitmentBulletInner"><a href="#" class="a-link-normal hsx-rpp-fitment-focus">Enter your model number</a>to make sure this fits.</span></span></li><li><span class="a-list-item"> The HA7 is a 4-in-1 design operates on 1/4 stereo 1/8 stereo and 1/4 mono and 1/8 mono. </span></li><li><span class="a-list-item"> Use in groups with a listening center jack box. </span></li><li><span class="a-list-item"> Impedance: 170 Ohms. </span></li><li><span class="a-list-item"> Frequency response: 18-20k Hz. </span></li><li><span class="a-list-item"> Cord: 3 meters. </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/41cPVGue2HL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41HglGuJVvL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41BFmp9ooUL.jpg" noproxy>