This rate is calculated on the basis of after sales requests for failure within a period of 30 rolling days. The higher quality your products have, the fewer after-sales requests you will see. We will also be able to monitor the details of any recurrent problems you face in order to find the best solution. Bear in mind that this rate is strongly related to your test solution. Your Quality Account Manager will be able to support you to find the best solution. If you're mainly facing battery issues, Back Market can propose you a high quality standards battery supplier. Do not hesitate to contact your Account Management team, who will be able to send you the full documentation.