Earlier this year, I picked up a replacement battery from for my 2012 MacBook Air from an eBay seller called "laptop-better-battery". The battery is now completely dead. Supposedly, they have a 3-year manufacturer's warranty. At least that's what their listings say. I've messaged them several times only to get crickets. They've even blocked me from buying another battery. Shady pricks, no? The only thing I can do now is recommend that no one buys from these jerk-offs.