The black version of the Sony MDR-1A Premium Hi-Res Stereo Headphones use 40mm Aluminum coated Liquid Crystal Polymer (ALCP) dynamic drivers to deliver a frequency response of 3 to 100,000 Hz, making them suitable for reproducing the information found in high-resolution audio at higher sample rates. Additional advancements include the use of 4-conductor cable for better signal separation, ergonomic earpads for long-term comfort, silicon rings around each moving axis for smooth and the option of adding cables engineered by Kimber Kable (MUC-B12SM1, MUC=B30UM1, MUCB20BL1).The headphones come with a carrying case as well as a detachable Android smartphone in-line remote control cable with electret condenser microphone and multi-function button for answering calls and navigating media on your Android smartphone. You can even customize the functionality of the remote using the SmartKey app available from the Google Play and App Store."