Here in the South where lead sealed vents are usually found ( although other places use them also) we have a lot of rain in the summer, and that rain can really get into your decking. The attached picture shows the gap between the outside of the vent pipe and the inside of the lead thats been chewed open. Thats a big gap for water to run right into the roof decking. It can really rot a roof badly over time. Dont let this happen, Critter Quitters repair damaged vents, and protect undamaged ones. Homedepot.com and Amazon, we ship the same business day.