Product maintenance is a post under the Engineering Services Department. It is mainly responsible for receiving, repairing and warehousing the repaired products, statistic the failure information of Engineering maintenance, and provide data support for the improvement of products and services. At the same time, it is responsible for dialing or answering telephone calls from customers and salesmen, answering questions on product maintenance, supervising maintenance progress, doing well maintenance follow-up work, ensuring product maintenance quality and meeting user requirements.