In terms of technology, most of the existing domestic middle and low grade products can replace imported products, and the reliability index of high-grade products, that is, the average trouble-free running time, is about one or two orders of magnitude different from that of foreign products. In measuring accuracy, the existing domestic products and foreign products generally differ by an order of magnitude, although at present there are domestic instruments and imported instrument precision of the precision of the same, but the real use of a period of time after the accuracy is relatively cheap. Due to insufficient research on basic technology and manufacturing process of instruments in China, some key technologies affecting reliability, such as precision machining technology, sealing technology and welding technology, have not been well solved up to now, resulting in unstable and reliable performance of products, especially high-grade products. In terms of function, at present, the intelligence degree of foreign products is quite high. Through the digital processing of the original information, the influence of external interference on the information is better eliminated, and the environmental resistance of products and the authenticity of measurement are improved. And domestic existing product intelligence level still is inferior. In addition, the network of products in foreign countries has entered the practical stage, and China is basically in the initial stage, so that the performance and function of products lag behind.