We bought the batteries associated with this review for an EGO backpack sprayer. We used the sprayer for one day. After that it stopped working. Power + Parts handed exchange responsibility off to the manufacturer, who appears to have outsourced customer service to someplace where there's limited product knowledge and language skills. I was required to submit an invoice form to start the exchange process. That form did not come with the backpack sprayer and was not contained in any of the correspondence received from power + parts at any point, which meant I had to contact power + parts separately to have that document sent so I could start the exchange process. The process seems to be going pretty slowly at this point. I submitted a few days ago and haven't heard anything about a new unit shipping. At this point I definitely recommend looking for a supplier that will perform their own exchange rather than purchasing from Power + Parts.