Our 3M™ Fire Barrier Moldable Putty Pads MPP+ Are A One-Part Firestop Material Used In Various Fire-Rated Assemblies, Such As Electrical Box Protection. Designed to Prevent The Spread Of Fire, Smoke and Noxious Gasses, This Intumescent Material Comes Ready to Use In Convenient 1/10 (2.54 MM) Thick Pads That Are Conformable By Hand With No Mixing or Tools. Pads Are Firestop Tested Up to 4 Hours.