Abstract: A valve comprising a shoulder, a movable check member having a wall facing the shoulder and a coupling member. The movable check member is adapted to prevent fluid passage through or out of the valve when in contact with the shoulder. The coupling member is adapted to displace the movable check member away from the shoulder responsive to the pressure being applied on the wall exceeding a predetermined threshold. The coupling member is further adapted to retract and maintain the movable check member secured against the shoulder responsive to the fluid flow pressure at the wall dropping below the threshold.