Today my a119 with a clip on cpl filter arrived. The filter didn't seem to do much, so I took it off and held it up to my lcd computer monitor. At about a 45 degree angle it completely block out the light from my screen.....and this is a proper Viofo cpl, it has clearly been put in wrong. I can easily slide the filter out and turn it, I just need to figure out if it needs to block the screen when vertical or horizontal, I'll just have to try both ways and see what works.