XINGLT MacBook Air Battery:Cobalt Proportion 99% ;The higher the proportion of cobalt; the better the performance of the battery;The manufacturing standards and testing standard are the same as those of the original battery supplier New Upgrade 3.0:Battery for macbook air 13 inch with Japan High Performance Electric Core;7.4V Capacity: 7200mAh 53.28Wh(Compatible with 7.6V 55Wh and 7.4V 53.28Wh) Package with one Macbook battery,one keyboard protective film,two screwdrivers,four helper mat,ten replacement screws