What are vlier plungers SPRSN250P-501& SPRSN250P-502?

These are very special parts!  they come with  a leadtime of 9-12 weeks. We do require an end user statement when you place a PO for SPRSN250P-501   &  SPRSN250P-502 ; furthermore, as with any special part, these parts may be subject to ITAR and/or EAR. EXPORT-CONTROLLED-WARNING: Hardware and/or technical data contained herein may be regulated under the International Traffic in Arms Regulations (ITAR) or the Export Administration Regulations (EAR). These parts may not be exported to foreign nationals without first complying with the export license requirements of the ITAR and/or EAR. Include this notice with any reproduced portion of this document.