English pronunciation, [_kw_tro_], quattro is a four-wheel drive technology trademark registered by Audi brand of Volkswagen, which is only used on Audi models. This is full-time four-wheel drive technology. At present, this system has been updated six times, which provides very strong stability and power for Audi vehicles. Audi brand is a luxury car brand in Germany. Its logo is four interlocking brands. Now it is a subsidiary of Volkswagen. Audi is headquartered in Ingstadt, Germany, and has many branches in China. Audi Company was formally established on June 1909, and the vehicle founder was August Hoch. Million car purchase subsidy