Altec Lansing AHP512 Closed Ear-Cup Stereo Headphones - 40 mm Neodymium Drivers - 3.5 mm Plug Performance for your most demanding applications! Superior quality audio reproduction. For studio and personal audio needs. High performance 40 mm neodymium drivers deliver a wide frequency response and bass you can really feel! Handy in-line volume control regulates audio level. Closed ear-cup headphone design improves clarity and minimizes ambient sounds. Comfortable! Adjustable deluxe padded headband and leatherette ear pads provide long lasting comfort. Performance specifications: Connection, 3.5 mm plug; Frequency response, 20 Hz - 20KHz; Impedance, 32 ohms.