Classified to U.S. and Canadian safety standards by Underwriters Laboratories Inc. for use in through-penetration
firestop systems, FlameStopper fittings meet UL
standards for low smoke leakage and are rated suitable for use in
plenums (air handling spaces). Their design makes is easy to add
or remove cables. FlameStopper fittings can also be used with any wall thickness and
provide a clean, professional looking installation.