KOSTER 2 IN 1 acts like a single component injection resin if it comes into contact with water. In this case, it reacts to form a highly elastic foam. KOSTER 2 IN 1 acts like a two component injection resin under dry conditions. KOSTER 2 IN 1 remains elastic after reacting. It is able to follow crack movements and seal cracks permanently with an elastic polyurethane solid resin without the need for follow-up injections. KOSTER 2 IN 1 is a fast reacting foam for the short term closure of leaks as well as an elastic solid resin for permanent closure of cracks. KOSTER 2 IN 1 therefore combines two resins into one product. KOSTER 2 IN 1 is solvent free and is resistant to hydrolysis.