My alarm clock glows a bright white-blue, and it was keeping me awake. I remembered from when I worked in an astronomy lab that red flashlights preserved night vision, so I figured I would try to put some red film on my alarm clock to help out. I bought this, and it works great. I trimmed to the size of the face of my clock and then taped it on with electrical tape around the edges to keep any light from escaping around the side. I had to use three layers to make it dark enough, but now I can sleep peacefully, and when I wake up, I can still see my clock. The numbers glow a dark red like on a regular clock now. I'm thinking of trying out another sheet as a night overlay on my tablet so I can read books on my screen in the dark without hurting my eyes.

I must say the build quality is excellent. It is a thick tough sheet of plastic. As it arrived, it was protected by plastic wrap on both sides of the sheets. I used it to wrap around a lantern as ambient light for night time photography. I knocked off two stars because the color is not red. It is way more orange than red. With a white light behind it, you get a solid orange. At first, I thought it was just my eyes but six photographers in the group all agree, it is orange.

The product is good. I wish they were thicker. I used them to make red lenses for flood/spot lights. I had to add about 5 layers to get a solid red like. Don't forget they have a plastic film on both sides.

Great for determining color value for watercolor painting. I mounted a full and 1/2 sheet of this gel filter between two pieces of poster board. I also cut one sheet into fourths and placed them in an envelope for easy access. Makes it easier to use.

Good quality filters, used to cover laptop screen and other obnoxious LEDs for astrophotography. Have a protective film on either side which ones removed gets rid of the cloudiness. Thick enough that its not flimsy like a piece of paper, but still easily bendable. If bright light is coming through its a bit more on the pinkish/orange side, not bad my any means considering their thickness and price, just double up.

Perfect for tinting my ground lights for the holidays.

Works well as light filters, both sides have a protection film on them that will peel off and make the film much clearer.

The filters are cloudy, they're not a true red, and they're not returnable. One of my worst ever purchases on Amazon.

Fade and lose colour after first nights use . I will not buy again

product as described