So far I havent been able to charge anything with this charger...I tried to use the 50 AMP selection to start a Mountaineer that had been sitting in the driveway for a while. It set off the Alarm system and never came close to turning the engine over. I tried slow charging and no better. Pay a little more and get a good charger. I will keep it and see if it will charge my mower battery..if not I will give it to someone.