What is the part number for the Waters Two-Position Six-Port Switching Valve? - WKB5919 Last updated Save as PDF Share Share Share Tweet Share Article number: 5919 ENVIRONMENT Waters Column Switching Valve (LabPro). ANSWER 417000118 (VLV, SWITCHING, 2-POS, PEEK, 1 LINE TTL) is the peek version. WAT050046 (VLV, SWITCHING, 2-POS, SS, 1 LINE TTL) is the stainless steel version. ADDITIONAL INFORMATION Waters' Two-Position Six-Port Switching Valve Information Sheet.