The Hamilton Electronics HA5USB starts with Hamilton's HA-5 headphone and adds integrated USB Sound. Use these headphones with any USB-equipped computer. Soft leatherette style washable, replaceable ear cushions, easy-to-wear design and swivel ear cups all contribute to longer fatigue-free use. Comes in easy to mark medium gray color. Specifications: * USB 2.0 Compliant, * Impedance: 170 ohms, * Speaker drivers: 57mm cobalt magnet type, * Headphone frequency response: 18-20k Hz, * 2 Meter Cord, * Windows 7, Vista and XP Compatible (Latest service packs recommended), * Mac OSX Compatible (Latest updates recommended), *Durable leatherette ear pads, * One (1) year warranty.