CHINA RUIAN RIYI VEHICLE PARTS CO.,LTD. was founded in spring 1996 ,which is specialized in producing and researching all kinds Mass Air Flow Sensor and crankshaft position sensor 。we are the first manufacturer in China ,Our range of Mass Air-flow Sensor is the most comprehensive and available in China. we have more than 270 items and 50 items air mass sensor and Crankshaft position Sensor at present .we are still researching many new products.