Zoronic Mobile Battery For Vivo Y21/ Y21S / B-S1

New Lithium Ion batteries must be FULLY CHARGED and FULLY DISCHARGED 2 to 3 times, before being FULLY CONDITIONED. Please remember that a new Lithium-Ion battery's full performance and longevity is only achieved after 2 to 3 complete charge and discharge cycles. After you go through 2 to 3 cycles, you'll never have to condition your battery again! *All talk and standby times are approximate, depending upon carrier's network settings, signal strength, and features selected. Talk and Standby times will be lower in Analog mode as noted above. We certainly do appreciate your business and if you are satisfied with our product and service, please provide us a positive feedback . Your support is the greatest motivation for us. We believe that any problem could be resolved through communication.We commit to offers you the best products and services.Please be assured that we will always take full responsibility. Thanks you very much.