The difference is Scotch® Tape! Clearest Film, Reduces condensation, Stops cold drafts, saves heating costs. Available in a variety of indoor and outdoor window sizes. 3M™ Window Insulator Kits keep cold drafts out and warm air in through heat shrink window film and Scotch® Window Film Mounting Tape. 3M™ window kits have the clearest film and stay up all season long with Scotch® tape technology.