If you need the integrity of a firewall, without adding caulk or putty after the cables have been installed, look to FlameStopper thru-wall fittings. Redesigned for both new installations and retrofits, these fittings combine a built-in fire-stopping intumescent material with an enclosed thru-wall penetration. They meet UL tests for flame, temperature and smoke, as well as for use in air handling spaces (plenums). Once installed, FlameStopper fittings allow you to add or remove cables easily, without risking unseen and potentially dangerous gaps or voids that can occur with caults or putty.
FlameStopper thru-wall fittings consist of two box assemblies, each with adjustable steel doors. The boxes are fitted to EMT conduit and cable pass through a block of intumescent material inside each assembly. At 375 the material expands, creating a hard char that fills voids around the cables and stops flames from penetrating the opening. FlameStopper thru-wall fittings are eay to install and inspect and work seamlessly with Legrand/Cablofil cable management products.