This is a very versatile charger/inverter system. I think it’s discontinued from DeWalt. But wanted to point out that you NEED to have 4 batteries installed in it to use it as an inverter (i.e. to generate AC power out). However it will charge 1-4 batteries so it’s useful as a charger too. But you should have a stock of (at least 4) DeWalt 20V or 20/60V batteries already for this make sense; it would be prohibitive to buy new batteries just for this purpose. Most people who use DeWalt tools a lot already have a bunch of batteries from various combo deals that come up – especially now around the holidays.