Abstract: A pump configured so that tools are not required to remove the pump head and disassemble the plunger. A single large hand operated knob or head nut facilitates tool-less pump head removal. The pump head is guided into position in a manifold and held in place by the hand knob. The manifold is designed to receive all the external fluidic connections made to the pump head. Fluid paths to the pump head have been replaced with miniature face seals which facilitate high pressure sealing between the pump head and manifold. Low pressure tubing seals reside in a seal wash chamber or housing and are not attached to the head, eliminating the need for tooling to disconnect them during pump head removal. A tool-less plunger mechanism includes a nutcap assembly having a plunger socket receiving a plunger assembly including a sapphire plunger fixed to a plunger holder ball accommodated by the socket. The plunger assembly is captured within the socket by a plurality of cams.