DuraVent Type B Gas Vent Wall Thimble - For Vent Pipes with a 4-Inch Diameter - 4GVWT: This unit necessitates a venting pipe with a 4" inner diameter. When it comes to satisfying construction codes and safety requirements, having building items that assist you meet those laws and standards makes the process much easier. When installing a gas vent through a combustible wall, DuraVent has produced a wall vent thimble that meets the clearance standards. Using a type B gas vent wall thimble will help you seal the area around the vent as this model is adjustable for walls of 3.5" to 6" thickness. 4" Dura-Vent Type B gas pipes are compatible with this device. This wall thimble meets the standards in terms of quality and efficiency, and it comes with a 25-year warranty.

Provides required combustible clearance for through-wall venting For use with 4" Dura-Vent Type B Gas Vent pipes Adjusts to accommodate walls with 3.5" to 6" thickness 25-year warranty