Properties:

A tubular item specifically designed for directing the flow of a fluid, and must accommodate a cap (as modified) or breather on one end. the opposite end has provisions for mounting directly on, or indirectly through a pipe, tube, or hose to a stationary or portable tank or reservoir (as modified); an engine crankcase; radiator; transmission housing; and the like. it may have means for overflow. for items which do not accommodate a cap (as modified) or breather see tube; pipe; or hose (as modified). see also filler neck, aircraft components and filler neck, vehicular components.