SIS440 Caulk is the proven leader in the marine industry and was developed specifically for teak deck seams. It is a one-part, paste-like neutral cure formulation and when exposed to moisture in the air, it reacts to form a tough, flexible solid rubber compound. The sealant does not sag during cure, and has excellent temperature stability and chemical resistance once cured. Because the sealant is neutral cure, it is non-corrosive to all substrates.