In order to ensure the highest level of quality for our customers, we conduct comprehensive quality control measures prior to shipping, which include rigorous testing and inspection procedures. These measures are designed to minimize the occurrence of any defects or dead-on-arrival units, providing our customers with a reliable and high-performance product. It is important to note that, as an aftermarket modification, our battery is not covered by any warranty offered by the original equipment manufacturer (OEM) of your device. However, we want to reassure our customers that each unit is carefully tested before shipment to ensure its optimal performance.