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Carlisle’s FleeceBACK® KEE HP polyester reinforced membrane is tough, durable, and versatile, making it ideal for a wide variety of re-roofing and new construction projects. FleeceBACK KEE HP polyester reinforced membrane offers exceptional weatherability, flexibility, and toughness due to its polyester reinforcing scrim, polyester fleece backing, and DuPont® Elvaloy® KEE HP copolymer. The polyester reinforcing scrim provides the sheet with added breaking strength, tear strength and puncture resistance for fully adhered or mechanically attached applications; the fleece backing adds to the puncture-resistance of the membrane and provides a built-in separation layer against rough concrete decks or existing asphaltic-based roofing systems. Elvaloy KEE HP, a solid plasticizer that will not migrate out of the sheet over time, helps to ensure the membrane remains pliable and weldable as it ages and reduces the amount of smoke generated during the welding process.