Review title is Search Google "Norelco T770 battery" before buying... [SEP] Not much more to say. Nice trimmer but. The battery loses it's ability to hold a charge after a year or so. Norelco provides no solution. In case you're saying to yourself "I'll use it plugged in." Think again. It does not work at all when it's plugged into a outlet. That's only for charging as long as the battery lasts.