Charger worked well for about 2 months. We bought batteries and a charger at the same time. Electric scooter batteries only last a year. We thought the batteries were dead. Checking the batteries at Autozone last night showed one battery at 100% and the other at 2% but none were bad. We got home, I checked the charger output and found that one side wasn't charging. I tried the charger from a friend's chair and it charged on both sides. It took about 3 hours to fully charge, giving the chair a "new” life. I would not recommend this charger to anyone.