Epoxybond Pool Putty is a unique two-part, hand-moldable epoxy putty specially formulated for concrete or gunite pool repairs. The convenient cartridge form provides a simple, equal mixing ratio (1 to 1). Just cut, mix and fix. There is no need to drain pools to repair leaks and cracks because Epoxybond Pool Putty hardens under water. Once cured, it will not shrink or sag.