A gas lift valve that is usable with a subterranean well includes a housing, a
valve stem and at least one bellows. The housing has a port that is in communication
with a first fluid, and the valve stem is responsive to the first fluid to establish
a predefined threshold to open the valve. The bellow(s) form a seal between the
valve stem and the housing. The bellow(s) are subject to a force that is exerted
by the first fluid; and a second fluid contained in the bellow(s) opposes the force
that is exerted by the first fluid.