A1527 A1705 Replacement Battery Battery Type: Li-Polymer Capacity: 5300mAh/40.02Wh 7.55V Newest 4.0 upgraded OEM Battery for macbook retina: Japan High Performance Electric Core and Upgrade chip. Up to 1500+ recharge cycles over the life of the battery-More than 5+ Years. Overcharger and Discharger Circuit Protection, Ensure fast charges and low power consumption