a sanitary pump and sanitary valve is provided employing a dual action piston for providing a constant pressure metering and delivery of fluids utilizing a drive shaft positively driven and controlled by a drive motor for sanitary applications . the novel sanitary pump may be fabricated from stainless steel , glass , plastic or other materials which do not include surface imperfections that would allow the growth of bacteria or allow the contamination of foods , medicines and other products that may be precisely metered by the novel sanitary pump . the novel sanitary pump includes novel sanitary check valves for opening and closing a high speed dependably and reliably and cycles up to 200 cycles per minute and preferably in the range of 60 to 160 cycles per minute by providing guides for maintaining check valve stem stability . the novel sanitary pump further include compression seals for sealing the drive piston to maintain high reliability and dependability in high speed constant pressure applications .