A double walled polycarbonate liquid holding vessel. The vessel may have
an inner wall and an outer wall that are coupled to each other in a
manner that defines an air tight gap therebetween. A resealable unit may
be provided with the vessel that permits resealable access to the
interior of the inner wall. The outer wall may be multi-section or single
section, and various techniques may be used to conceal joints used to
mount the outer wall to the remainder of the vessel. Various embodiments
are disclosed.