In this web content, the author discusses a fascinating feature of their toothbrush head: an NFC chip that counts the amount of time it has been used for. Surprisingly, after 360 minutes of use, the chip signals that the head needs to be replaced, regardless of its actual condition. However, the author reveals that the counter can be reset by sending a specific message from a phone to the toothbrush head. The process involves scanning the head with an NFC Tools app, copying the serial and part numbers, generating a password, and sending an NFC command to the head. This unique functionality may be seen as a bit insane, but it certainly adds a clever level of innovation to the toothbrush.
https://nonnullish.pages.dev/posts/resetting-the-timer-in-my-toothbrush/