Metacaulk putty is a moldable non-curing single component fire-rated material for through penetration firestop systems. Seal around cable, electrical conduit and metal pipe through fire-rated walls, floors and blank openings to prevent passage of smoke, flame and toxic gases. Putty applied by hand and easy to install; no special skills or additives are necessary for installation. Moldable feature adds to quick install. Intumesces when exposed to fire, forming an insulating char; rated for up to 3 hours in accordance with the ASTM E 814, UL 1479 and ULC/CAN4-S115-M test standards;. Putty sticks have sound transmission Class (STC) Rating 60. For interior use; no mixing necessary; adheres to all common surfaces. No asbestos fillers; putty comes in a simple liner; 2 year shelf life. FOR THE TRADESMAN: RectorSeal is recognized as a leading provider of quality solutions for the professional trades serving heating, ventilation, and air conditioning (HVAC/R), plumbing, electrical, and construction markets. Metacaulk Putty Sticks are used to seal around penetrating items through fire-rated walls, floors and within blank openings. For use with electrical cables, conduit and metal pipes.