1)As it has the rapid shut-up for freely opening function and counter waiter of disk at the minimum water head to disk of double-eccentric strusture, protection for valve, pump, pipeline closed according to 2nd stage by cushion of hydraulic pressure or air pressure could be perfectly settled.

2)If it will be compared to the same caliber size of check valve, since it will decrease about 4~7 times of installation area, it is clear that the cost decrease will give us as shortage of construction period.

3)Since weight of check valve will be installed width a max light weight by improvement of structure and shortage of distance, it is excellent forinstallation and transportation.

4)As attached the hydraulic pressure device, other than cushion cylinder of hydraulic or air pressure, it is excellent for mutual exchange to be added effectiveness of many functions, such as function of non return valve and urgent shut-up of hydraulic electric driving.