Drylok, 4 lb, interior/exterior fast setting hydraulic cement, mixes easily with water, sets in 3-5 minutes, stops the flow of water through cracks & holes in masonry surfaces, reduces radon gas penetration, seals floor & wall joints & settlement cracks in masonry walls, anchors metal to masonry.

• Mixes easily with water - sets in 3 to 5 minutes
• Use to patch mortar joints, cracks and holes in masonry walls
• Stops active water leaks
• Expands as it dries to lock in place