End cap section (10) for use in the construction of a configurable pressure vessel (80) and the vessel constructed thereof. The vessel having an interior volume and including at least one such end cap section joined to a second section. The end cap section (10) has a tubular wall (12) extending from an enclosed first end (16) to an open second end (18). At least one mounting pad (30) is positioned on the outer surface (20) of the wall on the enclosed first end (16) thereof. Such mounting pad has a base portion (32a-e) supported on the wall (12) and a generally tubular stub portion (34a-e) extending outwardly from the base portion intermediate a proximal end adjoining the wall (12) and a distal end (40a-e) configurable for connection to a fluid component (90). With the stub proximal end being closed by the wall, such end is openable through the wall to provide a port opening into the interior volume of the vessel.