Check the listing for details. SELKIRK Corp 187704 Wall Thimble, 4 Inch. Condition: New. Listed at 27.90 USD. SELKIRK Corp 187704 Wall Thimble, 4 Inch Product Description 4" 4RV-WT Wall Thimble. Adjusts 4-1/8" to 7" to fit wall thickness. Round Type B gas vent. When installed according to manufacturer specifications, the wall thimble provides the required 1 inch air space to combustibles. Tested and listed per UL-441 for installation as type "B" and B-W gas vents to be installed in single and multi-story buildings. From the Manufacturer 4" 4RV-WT Wall Thimble. Adjusts 4-1/8" to 7" to fit wall thickness. Round Type B gas vent. When installed according to manufacturer specifications, the wall thimble provides the required 1 inch air space to combustibles. Tested and listed per UL-441 for installation as type "B" and B-W gas vents to be installed in single and multi-story buildings. Features 4" 4RV-WT Wall ThimbleAdjusts 4-1/8" to 7" to fit wall thicknessRound Type B gas ventWhen installed according to manufacturer specifications, the wall thimble provides the required 1 inch air space to combustiblesTested and listed per UL-441 for installation as type "B" and B-W gas vents to be installed in single and multi-story buildings USA SHIPPING eBay estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.