Abstract: A pump for dispensing fluid from a dispenser includes a base in fluid communication with a source of fluid carried by the dispenser and with the atmosphere. The pump includes a base attachable to the source of fluid, a flexible transparent dome attachable to the base in overlying relationship therewith and in fluid-tight relationship, and a retainer attachable to the base in partial overlying relationship with the dome to retain the dome on the base. The pump also includes valves for selectively opening and closing the pump to fluid communication with the source of fluid and the ambient atmosphere.