Acrylic primer designed to promote adhesion of STOPGAP levelling compounds to non-absorbent subfloors. STOPGAP P141 contains recycled uPVC pulver that dries to a hard, textured surface to enhance bond performance. STOPGAP P141 is recommended when applying STOPGAP 600 over non-absorbent surfaces at thicknesses over 20mm. It is suitable for use over normal underfloor heating and is pigmented yellow for visual control of coverage uniformity.