In the very beginning, we could only produce diaphragm check valves with only one specification. Now, we are able to manufacture the mini-type diaphragm check valves with all the five interface specifications of "1/8", "3/16", "1/4", "5/16" and "3/8". Besides, we have developed the spring check valves and the oil-way check valves, which are on continuous improvement. Apart from this, our company has spread to the manufacture of micro-diaphragm pumps and the non-touch liquid level switches.