Designed for exterior use as a stain-blocking sealer to minimize the “bleed through” of wood tannins and common household stains. Stain Blocking Primer hydrates wood with resins that protect against the elements, reducing damage by water and ultraviolet light degradation. For added protection apply a coat of Sansin’s ENS Deep or White Base which is available in a large variety of colours. Excellent topcoat holdout, low VOCs and non flammable.