An annular vent sleeve valve communicates between the casing annulus and producing formation. The valve is a hydraulically operated sliding sleeve device like a surface controlled subsurface safety valve with a hydraulic piston and a power spring to maintain the valve in a normally closed position. The valve is used with a bull plug on top or as an annular safety valve by providing annular bypass while control pressure is applied. With an electrical feedthrough device, this valve functions through a single packer mandrel as an electric power cable passage and annular bypass. On a dual hydraulic packer, the valve operates by a common hydraulic control line that sets the packer and operates the tubing-retrievable safety valve. Hydraulic pressure from the control line shifts the valve open to create a flow path across the packer in the annulus. Spring force closes the valve upon loss of control-line pressure to the piston. If the valve becomes inoperable or closed, an emergency shear feature allows fluid to be pumped into the producing formation from the annulus. Applications » Gas lift and electric submersible pump situations Features » Accurate fluid level shot during pumping because of large ported area through the vent sleeve » Maximum gas vent flow area allows increased gas flow rates and lower circulating pressures » Valve will shut off flow from either direction — production or injection *description excerpted from manufacturers catalogue.