This is an R-only listing, with the battery replaced with a genuine new battery! The version is the latest version, 2.1.0 (^-^) Thank you for viewing! I run a battery replacement business in Hiroshima! My name is Chika, a repair and electrical specialist (*^^*) This has been replaced with a new genuine battery (*^^*) It seems there are some unscrupulous operators out there, and a friend consulted me because their battery failed for the third time. I disassembled it and found that a cheap, non-genuine battery was installed, designed to break down after only a few uses. This is definitely a genuine new battery, so there shouldn't be any problems, but just in case, I'm offering it with a warranty (*^^*) I will also include a warranty card, so you can rest assured (*^^*) I offer a free one-week warranty, so please feel at ease (*^^*) Additional long-term warranties are also available, so please feel free to contact me (*^^*) I also accept repair requests, so please feel free to consult with me (*^^*) I appreciate your kind words! Thanks to the overwhelming response, I've received very positive feedback, so I've significantly reduced the price! Please consider it (^-^) ⚠ We do not accept returns for issues such as incompatibility due to version differences, so please make sure to confirm before purchasing m(_ _)m I may be able to accommodate your desired version, so if you have a request, please feel free to contact me (^-^) Wireless Noise Canceling Stereo Headset WF-1000XM4 Brand: SONY Wireless Noise Canceling Stereo Headset WF-1000XM4 Brand: SONY Wearing style: Separate left and right, completely independent Earphone/Headphone type: Canal type Structure: Sealed type Wireless/Wired connection: Wireless Earphone/Headphone functions: Noise canceling, Hi-Res, Microphone, External sound capture, Waterproof, splash-proof, Remote control wf-1000xm3 wf-1000xm4 wf-1000xm5 wf-sp900 wf-ls900n wf-l900