Rubberflex S 1C is a one-component, low-slump, highly crack-bridging, bitumen-free, water-free, and solvent-free special sealant based on silane-modified poly- mers. The product is moisture-reactive and cures without forming bubbles. For this reason, Rubberflex S 1C can be used almost regardless of weather conditions. Curing is guaranteed even at very high air humidity. Due to a special adjustment of the raw material components, the material is UV-stable.