The Pipe Collar by Wil-Mar Products was developed to eliminate the problem that exists when sealing a vent pipe to a roof flashing. The Pipe Collar is made from a special EPDM rubber compound that meets ASTM D-2000 Standards for hi-lo temperature, oil, ozone and sunlight resistance. It is warranted to last as long as any of the roofing systems being offered today. The Pipe Collar's unique design allows it to slide easily down any pipe, (i.e. plastic, copper, galvanized, etc.) but stay firmly attached to the pipe so that it moves when the pipe moves, and the seal is completely weatherproof. Because you only attach the Pipe Collar to the pipe and not to the roof flashing, you eliminated the need for tape or mastic that wears out, breaks or pulls the flashing away from the roofing causing costly roof leaks.