Stops flowing water in 3 to 5 minutes. Nonshrinking; will set up under water. Exceptional structural strength. Dry powder form, just add water. Easy-to-mix and put in place; requires no special equipment. Nontoxic when set. Nonmetallic; will not rust out or deteriorate. Perfect for plugging leaks in basement walls, swimming pools (underwater set), cisterns, fountains, walls, and chimneys.