A buddy of mine had these and I thought they were a joke, but after looking through binos with them on I was a believer. I orderd a set and now they live on my binos. They help reduce eye fatigue from light coming in on the sides when glassing, especially in bright conditions. They only issue you may have with them is if you wear glasses, then they might not work as well for you as it will puch into your glasses. But if you wear contacts or don't need glasses they work great!.
Good purchase. They are very helpful at blocking glare and fold back easily on one side or the other(or even both) if needed to prevent fogging. They also fit snuggly on the eyepieces. I do not use the clip at all because when clipped it still does not protect the ocular lenses and the clip can even create a lens scratching hazard. I fold the sides/overlap them so that when the binocular pack is closed, it holds the flaps in place and protects the lenses.