The SportaPro's weight is a mere 2.2 ounces, and the headphones boast a frequency response of 15 to 25,000 Hz, delivering (on paper, at least) quite a bit more bass than most home speakers can. Impedance is 60 ohms, with less than a 0.2 percent distortion and sensitivity of 103 dB SPL (with a 1 mW signal).
The SportaPro stereophones are collapsible and come with a carrying case, as well as both 0.125-inch and 0.25-inch jacks. Koss covers the headphones with a lifetime warranty.