SONY WF-1000XM4 wireless noise-canceling earphones. The earphones' batteries have been replaced with new ones. To ensure the next user can enjoy them for a long time, both the left and right sides have been fitted with new batteries, not just one side. In preparation for listing, the internal components were disassembled, air-blown, cleaned with alcohol disinfectant, and the contact points were cleaned. The items for sale are the earphones and charging case (as shown in the first image). The firmware is updated to the latest version as of now. Please understand that this is a used item. Please check the appearance from the images. If you are looking for a perfect item, please purchase one with a manufacturer's warranty. Shipping will be via Rakuraku Mercari delivery, which provides fast and reliable delivery tracking.