If you only pay attention to quality, you can choose instruments such as COD and ammonia nitrogen from Hash brand in the United States, and you can choose advanced brands for flowmeters. However, the prices of the above brands are relatively expensive.

However, domestic products such as Shenzhen Century Tianyuan, Nanjing Linde and Hebei Xianhe are of good quality and moderate prices.

Some small factories in China are even cheaper and can cope with the inspection by the Environmental Protection Agency.

There are two points to note. If it is for enterprise's own use, the Environmental Protection Agency has no requirement, so it is recommended to use the products of domestic manufacturers.

There is also a universal on-line monitoring instrument. The local environmental protection has recognized the brand, and you can only buy it according to their wishes, so that you can accept it smoothly and will not be forced to wear shoes in the future.