Spraying gun for atomising a liquid as well as disposable containers and insert for use in a tank containing said atomised liquid

A removable reservoir for a paint spray gun has an outer container (12) provided with an air vent (12A), a removable, self-supporting liner (13) adapted to fit within the container (12) and a lid (15) co-operable with the liner (13) to form a fluid reservoir (13). The lid (15) has an outlet (17) and a filter (19) that covers the outlet (17) whereby paint withdrawn from inside liner (13) when the reservoir is attached to a spray gun flows through the filter (19) and the outlet (17) to the spray gun. The liner (13) is adapted to collapse when paint is withdrawn from the liner (13) during operation of the spray gun.