Gripnail's Insulation Hanger easily install any type of insulation up to 3.5" thick to air ducts, metal buildings, concrete foundations - even to the underside of wooden roofs. Insulation Hangers are perfect for installing fiberglass or rubber insulation blankets or polystyrene board. Insulation Hangers have a sticker backing to make placing easier. They also have a unique Easy-Peel adhesive backing design so that there isn't any fumbling with the release paper.