Mylar sucks - very fragile, loses its reflectivity, 'fogs' after awhile ... I used the best DuPont 2mil Mylar, never again ... I'll go back to flat white reflective surfaces, unless my 'Luminix' experiment pans out ... 'Luminix' is a Mylar-like material, for building insulation ... unlike Mylar, it is tough, won't tear, or scratch, seems almost as reflective, but I'm not sure how good, yet ... it has almost invisible pinholes in it, so the building can 'breathe', so it would have to be applied to a wall, and not 'stand-alone' ... bought mine online from Home Depot, they don't carry the 4' wide rolls in their stores, only the 2' ... might be worth checking out :smokin: