Important notes: Item specs Part No:616-00507 Capacity:3174mAh/12.08Wh Voltage: 3.8V Type: Polymer Packaging: 1 x battery，1x tools Compatible with IPhone XS MAX A1921 A2014 A2101 A2103 1. It is recommended to fully drain and fully charge the battery especially during the first 3 charging and discharging cycles, doing so may greatly improve the overall life of the battery. 2. Before you buy the product, please confirm your mobile phone model again to avoid buying a wrong battery. 3. It is easy to replace old battery with brandnew battery. Please turn off your phone prior to replacement, carefully disconnect your old battery and then connect your new battery to the mainboard, please ensure battery is connected to cellphone well,easily install, no need to worry about the installation is too complicated. 4. Please install carefully. A charged lithium-ion battery can catch fire or explode if it is accidentally damaged. 5. If your phone constantly restarts and the logo flashes or is not charged. Probably the connection of the ribbon cable is poor. Please re-insert the ribbon cable, check the connector and clamp it firmly. If you have any questions or problems with our products, please let us know.