Mapei Primer G - 5 LitreSynthetic resin primer in water dispersion with a very low content of volatile organic compounds (VOC). Where to use: For treating gypsum surfaces prior to installing ceramic tiles. As an anchoring coat for gypsum based sprayable plasters. To improve the adhesion of smoothing compounds on cementitious or anhydrite and gypsum based surfaces. To provide uniform absorption in cementitious or gypsum surfaces.