DuraVent Type B Gas Vent Wall Thimble - For Vent Pipes with a 5" Diameter - 5GVWT: This unit necessitates a venting pipe with a 5" inner diameter. A thimble must be utilized when inserting a vent pipe through a flammable wall to provide support for the pipe and to protect the surrounding materials from the vent generated during operation. The 5 DuraVent Type B gas vent pipes are used to vent gas fireplaces, boilers, water heaters, and space heaters. The thimble adjusts to fit walls ranging in thickness from 3.5" to 6". A 25-year warranty is included with the item.

Provides required combustible clearance for through-wall venting For use with 5" Dura-Vent Type B Gas Vent pipes Adjusts to accommodate walls with 3.5" to 6" thickness 25-year warranty