I needed something to "sound" insulate a set of mufflers for my Generac and this stuff fit the bill. Bought one (12) pack of the 1" wool and used two layers, easy to cut with hand shears. Was advised to use screws with washers, but after making one side I felt the stress of the exhaust flow would have eventually scoured the wool from the sides. Also, the wool may be impervious to moisture, but it sure gets heavy when wet! I ended up redoing it and the other side with 1/2" hardware cloth under washers and screws. All in all, it made a large difference in sound!