Stop flowing water leaks, even under pressure! Plug troublesome cracks in masonry to stop seepage in just minutes. Rutland's dry mix hydraulic cement is a fast-setting mixture that stops water flowing through cracks and breaks in masonry surfaces. It works even when the water is under pressure. Use it to repair swimming pools, cisterns, frost damage, basement walls, or water storage containers. Its also perfect for use as an anchoring cement to secure bolts and machinery. Coverage: 1 lb. fills 17 cu. in. 6200 psi compressive strength.