Batteries died. It was a puzzle to disassemble it. It was booby-trapped with fragile self-destructing mechanisms like hair-thin wires ready to snap wrapped around the battery which had welded tabs soldered to wires. Requires surgical delicacy. Had to buy rechargeable batteries with tabs welded on where the tabs were not oriented in the direction the device was designed for so in one joint I had to put the soldering iron directly on the battery terminal. The battery pair costed 1¼ big macs because tabbed nippleless batteries are not a competitive market and only sold at retail prices. A new toothbrush probably would have had the same price.

I was able to do the job without breakage and it works. So I would like to send a very big fuck you to Philips who tried to force me to buy another toothbrush, which I bought before I started boycotting Philips due to their shavers having the same disrespect for a #rightToRepair.