Excellent product. The perfect primer for stone, tiles, and masonry. It works flawlessly with the Sikaflex 11FC silicone and creates an excellent and flexible joint with perfect adhesion and complete waterproofing. It is worth 100% of its price. The only, if one can call it a problem, is that despite the fact that it seals tightly with its cap, and I sealed it with tape, after 4 months when I needed it again, it had hardened. Probably when it comes into contact with air, it starts to dry out no matter how you protect it.