Zinsser WaterTite Hydraulic Cement is a fast-setting, professional-grade repair solution designed to stop active water leaks in concrete and masonry. This high-strength, cement-based formula expands slightly as it cures, creating a watertight seal in just 3–5 minutes—even on wet surfaces. Ideal for sealing deep cracks, patching holes, anchoring bolts, and repairing basement walls or foundations. Durable, easy to mix, and built for long-lasting performance, it delivers reliable waterproof protection where it matters most. 10 lb (4.53 kg) pail.