Metacaulk 1000 is a 1-component, general fire-rated sealant/smoke seal for construction joints & through-penetrations. Cures to elastomeric seal suited to dynamic motion. Stops flames/smoke/hot gas/water moving through joints & through penetrations. Metacaulk 1000 is a water based, extremely intumescent, non-sag caulking grade sealant that is easy to apply.