7 working days. Nanjing car booster coupon is issued by UnionPay, in the city of Nanjing to buy a car with, the audit takes a short time, need 7 working days. Nanjing, referred to as "Ning", the ancient name of Jinling, Jiankang, is the capital of Jiangsu Province, a sub-provincial city, megacity, the core city of the Nanjing metropolitan area, the State Council approved the determination of the eastern region of China's important central city, the country's important scientific research and education bases and comprehensive transportation hub.