Multipurpose Primer is an acrylic, latex-based multiple substrates primer for use with TEC® brand self-leveling underlayments. It may also be used to enable the bonding of other TEC brand surface preparation products and polymer-modified thin set mortars to difficult substrates such as metal, glazed ceramic tile, gypsum-based underlayments and concrete treated with certain types of curing compounds (silicate or acrylic resin curing compounds only) and well bonded epoxy coatings.