This specification covers the requirements for base materials (laminate and prepreg) to be used primarily for rigid or multilayer printed boards for electrical and electronic circuits. This document contains more than 50 separate specification sheets and now uses search terms to allow the user to find similar groups of materials from these specification sheets. This standard provides the user with additional information and data on printed circuit board materials that are better able to withstand the newer assembly operations employing higher thermal exposures, including those assembly practices that utilize the now commonly-encountered lead free solders.