AKG K240 headphones with 55Ω impedance and a frequency response of 20Hz - 20kHz. - Brand: AKG - Model: K240 - Impedance: 55Ω - Frequency Response: 20Hz - 20kHz - Color: Black/Gold I purchased these new on Amazon last May with the intention of producing music, but I ended up not doing so, and am now selling them. I used them for about a month, and then stored them in a storage room. Everything shown in the photos is included. Cleaned with disinfectant wipes and a blower. I have tested them by connecting them to a stereo and confirmed they are working properly. They play without any issues. The condition is also good, so please consider purchasing them. Thank you for looking.