499 waterborne, Mill Prime is a professional grade, interior primer that is formulated to have good hiding and filling properties, outstanding enamel hold out and is a great alternative to solvent borne white lacquer undercoaters. This high solids primer is easy to apply, sands easily,dries to a smooth finish and provides an excellent foundation for enamels on new interior wood, and as a primer for properly prepared interior wallboard, acoustical tile, cured plaster, brick and other masonry surfaces. This product has very low odor, dries quickly.