The 40L Aquaroll is manufactured to the same high specification as the 29L version but with the added advantage of a facility to connect via the mains adaptor kit directly to a mains water supply. The mains kit is an optional extra. Even without the mains facility the extra capacity is a must in modern caravanning.. The side opening can also be used as a convenient filling point when in use as a conventional water carrier. High quality tyres on deep rims give excellent ground clearance. Filler tube and handle included.