Hey there DIYers and pros! This SELKIRK wall thimble is exactly what you need for running your Type B gas vent through walls safely. It's a 4-inch diameter thimble that adjusts from 4-1/8 inches to 7 inches to fit pretty much any wall thickness you're working with. The really important thing is it provides that required 1-inch air space to combustible materials when installed properly - super crucial for safety. It's been tested and listed per UL-441 standards, so you know it's legit for both Type B and B-W gas vents in single or multi-story buildings. Whether you're installing a new furnace, water heater, or any gas appliance that needs venting through a wall, this thimble keeps everything up to code. The round design works perfectly with standard round Type B gas vent pipes. Installation is straightforward if you follow the manufacturer's specs - just make sure you get that 1-inch clearance right. Much better than trying to rig something up yourself that might not be safe. Solid construction that'll last for years without issues.
Free 30-day returns 
Free 30-day returns
