Thank you for viewing. ※ Software version is 2.1.0. If your earphones have a version of 2.0.0 or higher, they can be paired. Please be sure to check the version. This is a replacement with a new genuine ZeniPower Z55H battery. All operations have been confirmed. The results of 2 hours of continuous playback with noise canceling ON and volume at 50% are posted, so please use them as a reference when purchasing. There may be some signs of use, but there are no noticeable scratches or stains. Please check the photos. Recommended for those who have lost one side, have a malfunction, or find that the battery drains quickly. Be sure to initialize. How to reset and initialize: https://knowledge.support.sony.jp/electronics/support/articles/00264029 Please understand that the earphones are used items before purchasing. We will clean and disinfect with alcohol before shipping. Sony Model Name...WF-1000XM4 Other features...Noise canceling