Rainin SD200, SD300 / Varian Prostar 210, 215 Piston 10 mL/min.  This is NOT compatible with wash option.  OEM# for wash option is 3650010, R007101659.

This piston is suitable for all inert and non-inert pump heads. The piston assembly contains a Stainless Steel piston holder, but that portion of the assembly is never in the flow path.