When received, I found that the battery kept draining to zero when I left town for a few days, even with the Amazon/TekReplay generic power supply plugged in. After three trips to the Apple store, we determined that the generic USB-C power supply was not really compatible with the MacBook. Therefore, I had to purchase a 96W genuine Apple USB-C power supply ($79, obviously out-of-my-pocket). Now, this refurbished system works perfectly.