... of valve. Phosphating to improve corrosion resistance.Feature:Hydraulic actuator installed on the top of the bonnet ... the open and close of the valve by hydraulic pressureMetal seal between the body and bonnetBackseat ... with the performance of anti-corrosion,wear-resistanceLow operating torqueEnd Connection: Flange,Thread,Union,BWSize:1 13 ... Medium:Oil,Gas,Water,etc API 6A Manual Gate Valve, 6A Valve