1Applicable Earphone: This earphone adapter cable is designed specifically for IE40 Pro earphones, easy to connect and convert, with strong compatibility and has a wide range of applications 2Wireless Function: This adapter cable helps you convert original wired earphone into wireless earphone for use, and connect to your phones, tablets, laptops, and other electronic devices through BT 3Excellent Performance: The BT5.4 and low latency codec ensures the high wireless quality of BT, improves synchronization with compatible devices; The transfer distance is about 10m, meeting more needs 4User Friendly: Equipped with pre formed ear hooks that fit snugly against the ears, providing stability when worn; With controller and integrated microphone for controlling calls, volume, and music playback 5Wide Compatibility: The earphone adapter cable is compatible with phones, tablets, laptops, and other BT stereo transmitters; Built in rechargeable lithium ion battery provides 39 hours (75% volume) of play time