Abstract: A fluid flow control valve of the ball type has a unitary body moulded in an elastomer and defining inlet and outlet passageways and a spherical cavity accommodating a plastic, ball-shaped closure member. The closure member is located in the cavity by forcing it, together with its actuating spindle, through a bore formed in the body until it is sealingly located, as a snap fit, in the cavity, during which process the bore is resiliently deformed outwardly but subsequently resiles into contact with the actuating spindle. The valve may, thus, simply have a pair of injection mouldings and, relative to prior ball valve constructions, is therefore simpler and more economic to manufacture. The body is integrally formed with a peripheral external recess whereby it may readily be sealingly engaged, simply as a snap fit, in, for example, an aperture formed in the base or a compressed sir filter bowl, the valve acting as a manual drain valve.