Amazing product! It was pretty easy to apply, but an extra set of hands definitely helps. I watched the video online of how to apply to see exactly what to do. Even if you don't line everything up perfectly (I.e slight wrinkling/buckling) the hairdrying step makes it smooth as glass. I was surprised it didn't pick up fingerprint marks. Already can feel the difference!

First, the pack that's supposed to have enough film for "FIVE 3' x 5' windows" barely covers one 3' by 6' window. (Yes, I unfolded the film completely.) Second, the double-sided tape is low quality: the backing peels off when you don't want it to, and won't peel off when you finally do want to remove it. I'll trust Duck for their duck/duct tape, but never again for an insulation product.

Worst product of this type - EVER! Film is impossible to measure - sticks to everything and then tears with the slightest pressure. Wasted half the roll of film just trying to cover one window. And doesn't work well AT ALL with metal window frames set into drywall with narrow edges. I might as well have just covered the window with a piece of plexi-glass with weather stripping around it. Do Not Buy This Product!

Kit worked as advertised. I am worried about the paint pulling away from the molding if we need to remove the film later. I used a heat gun instead of a hair dryer like the instruction told me too. The hair dryer just took too long to get the film to shrink. You do need to keep the heat gun moving as you could blow a hole in the film if you leave it in one spot too long.

Many glowing reviews so I thought I'd give this product a try since my home has a ton of large windows that radiate icy cold temps during the winter. I recently obtained a Flir thermal camera to inspect leakage within my home. I thought it would be a great idea to use this to see if the window insulation kit makes a difference.This may not be relevant, but before installing the window insulation kit I applied a window film to one of the windows as I am in the process of making the front windows of my house more private. Personally I thought the window film would add a layer of insulation to the window, but that wasn't the case. In the end, after placing a window film and the window insulation kit, I saw barely a difference in temperature. To be more precise, the thermal camera actually displayed the side with no film and insulation to be 0.3 degrees warmer. This product may be great for someone that has some seriously drafty windows, but it didn't seem to do anything for my application.