TapeCase Heavy Duty Aluminum Foil Tape-Converted from 3M 438, is a thick 7.2 mil industrial grade metal foil tape used for protective applications, thermal conducting, splicing foils and patching aircraft and truck trailer skins. This product is optimal for applications that necessitate an aluminum barrier of 5.0 mil thickness. Featuring an acrylic adhesive, this product offers a long durable service life for both indoor and outdoor usage.