Abstract: A breast pump includes a housing, a suction unit mounted in the housing, a rippled funnel for engaging a mother's breast, and an adapter for interconnecting same. The adapter is configured to sealingly support the funnel, frictionally sealingly support a bottle for collecting milk, and frictionally sealingly engage the housing. The adapter includes a tubular protrusion/stem defining a passageway for communicating air from the bottle to the suction unit to create a vacuum in the bottle. A pair of "O" rings are positioned on the protrusion to sealingly and stably engage the housing. A check valve is located in the protrusion to prevent back flow of milk from the bottle to the suction unit. The housing includes an outer surface defining a hand grip, and vacuum adjustment controls including a wheel for fine vacuum adjustment and a vacuum releasing push bottom are conveniently positioned on the hand grip.