Pre-formed flange placed over a vent pipe to seal the roof around the vent pipe opening. Made of lead, rubber, or metal. Referred to by various terms {pipe boot/jack, plumbing boot/jack, and/or no-caulk or leads}.
They go on the roof for where pipes penetrate your roof. Pipes have to come up through your roof to service the house below. Every drain in your house has a pipe that penetrates your roof. to protect your home you want to put these on there to prevent water from coming in.
