Puredick&reg; New Laptop Battery for Asus C23-UX21 ZenBook UX21A UX21E -12 Months Warranty[Li-ion 4-cell 7.4V 4800mAh] Battery Type: Li-ion || Voltage: 7.4V || Capacity: 4800mAh || Cells: 4-cell 100% New from Manufacturer. Up to 500 recharge cycles over the life of the battery. Grade A cells ensure fast charges and low power consumption; Built-in circuit protection ensures both safety and stability. CE-/FCC-/RoHS certificated for safety,12 months warranty,professional technical support, efficient and always satisfied customer service 24 x 7 email support. Operation time:Same Battery life with Brand new original Dell battery.In reality, this will depend on the amount of electricity required by the device and how you use it.