Metacaulk 1200 is a water-based sealant designed for spray application. It allows fast, economical installation on long joint runs. Self-Leveling is made for horizontal applications and Caulk Grade is a non-sag sealant that is easy to applyMetacaulk 1200 is also an excellent, fire-rated acoustical sealant. It cures to an elastomeric seal suitable for use where dynamic movement is expected. STC rating 50, Tested in a UL 411 wall assembly/section to ASTM E90.