I noticed that I sometimes get glare off of the camera housing and from the front fender. I knew I wanted a polarizing filter for the K2 cameras. I borrowed an idea from this forum to use 1 inch heat shrink tubing. I purchased a package of polarizing filter paper and a 1 inch hole punch. I found a socket that had the right outside diameter - just under 1 inch. In my case, the socket is a 19 mm Craftsman brand. I have included a picture so you can see how simple this is. I also found that using a washer to temporarily block the heat from reaching the paper helps. Here is a picture of the material. (really cheap). I was pleased with the resulting video although it does slightly darken to overall image.