What are CLSI companion products? Victoria Phucas December 05, 2019 14:33 Updated Follow CLSI companion products include easy step-by-step instructions and visual illustrations for an overview of the recommended procedures. Shop our companion products by category on our online store. Related articles I have questions about the LQMS Certificate Program. Is CLSI an accredited standards development organization? What are the requirements to become a CLSI volunteer? Which membership levels have access to eCLIPSE Ultimate Access? What software is required to view the PDF documents I purchase?