Refillable pump dispensing container

A dispensing container for flowable material comprising:

• (a) a cylindrical upper body for containing the flowable material and having a first and second end opposite one another, the second end having an open mouth;
• (b) a cylindrical lower body having a first and second end opposite one another, the first end being telescopically mounted within the upper body, and the first end having a boss portion of a smaller diameter than a cross-sectional diameter of the lower body;
• (c) an orifice for allowing egress of the flowable material, the orifice being formed on the first end of the upper body;
• and
• (d) a piston sealingly slidable within the upper body, the piston being formed by a diaphragm having an upper and lower surface and a skirt surrounding the diaphragm, the upper surface facing the first end of the upper body, the flowable material being restricted to an area between the upper surface and the orifice, the lower surface in combination with the skirt defining a cavity consisting of a straight cylindrical wall along a length thereof, the boss portion of the lower body extending into the cavity, the cylindrical wall being formed with a plurality of ribs on an inner surface thereof projecting radially inward in a direction perpendicular to the lower surface of the diaphragm and frictionally engaging the boss portion of the lower body to establish a snug, frictional fit,