"Bestop's new Sailcloth Replace-a-top is 50% quieter than a factory denim top. The secret lies in the unique multi-ply Sailcloth fabric. Each ply plays a different role, but together they reflect road sounds, absorb wind noise, and prevent buffeting to create a silencing effect. In addition, the beefier Sailcloth fabric resists temperature-induced shrinkage, making cold-weather installations much easier. It also shows fewer waves and wrinkles than conventional tops and cleans more easily. (Only available for Wrangler 88-01)"

(taken from the Bestop Website: www.bestop.com)