Our 3M™ Fire Barrier Pass-Through Device Round Are One-Piece Hinged Metal Enclosures Designed to Prevent The Passage Of Fire, Smoke and Toxic Gas. This Easily-Installed Device Is Ideal For Firestopping Penetrations In High Traffic Areas Where Telecom, Data or Electrical Cables Are Frequently Added or Removed. Intumescent Material and Foam Smoke Seals Achieve A 3 Hour Fire Protection Rating.