If you want some warranty don't buy here.
I bought a Nikon Battery, it worked for 2 months, it was nor perfect but it worked. I had some minor issues (less capacity, more charge time, it stopped work when it was half full) but just keep using it.
I evaluated the buy because it seemed good (before the minor issues).
Then after 2 months the battery just stopped working.
Reported the situation to the seller. (https://www.ebay.com/usr/sunpower-fly)
Reported the situation to ebay.
Reported the situation to Paypal.
I will report this situation to Nikon. (It's not a Nikon battery but they say it is.)
In Europe we have a warranty of 3 years in this kind of products. Here it was a total loss of money and time for me.
I tried to change my evaluation of the seller but eBay does not permit.