The ALLPOWERS R4000 Portable Power Supply has a UPS (Uninterruptible Power Supply). When the UPS function is turned on, even if there is a sudden power failure, the connected electrical products will not stop and can be used as usual. R4000 UPS has the function of instantaneous power failure when switching, but if the switching time is long, it is only 15ms. Although the time is short, there is a momentary power failure, so it is not suitable for precision machinery or enterprise systems that handle important data, and you can live without worry.