1. Li-ion battery for Apple Watch Ultra 49mm A2749 542mAh 2. Best replacement for the original battery with comparable standby and talk time 3. The Li-ion battery provides excellent continuous power sources to your device 4. Use the authorized charger only 5. If you do not use the battery for a long time, please put it in a dry and cool place and make it full charged once every three months 6. Compared with Nickel-Cadmium battery, the Li-ion battery has no memory effect 7. Integrated microchip inside prevents overcharging and lengthens battery life 8. To reduce risk of fire or bums, do not disassemble, crush, short circuit, or dispose of it in fire or water
