Connect your smartphone to your headphones with microphone using the Onyx Series Auxiliary 3.5 mm TRRS Audio & Microphone Cable. The TRRS (tip-ring-ring-sleeve) plug provides an extra conductor over the stereo TRS plug, allowing you to carry both stereo audio and voice over the single cable. Unlike many 3.5 mm cables, the connector heads are very thin, allowing you to plug into a smartphone with the case installed. Bend tested over 5,000 times for proven long-term durability, it features aluminum connectors for an extra measure of durability.