HTGSupply 25 Foot by 4 Foot Super Thick Reflective Mylar On Black Poly Roll, 6.7-Mil Extra thick silver metalized reflective Mylar on black poly liner Construction: Highly-reflective metalized silver side ; lightproof black poly backing ; super heavy-duty, tear resistant 6.7-mil (.0067-inch) thickness Hangs easily using tape, staples, tacks, adhesive, etc. Please Note: This material does not produce a clear mirror image, and thus is not recommended for visual applications in which this quality is desired. Roll measures: 25' long x 4' wide