Sometimes you just need to block a tiny bit of stray light without pulling out some huge flag that will just get in the way.
That's where this little guy comes in. Unobtrusive, lightweight, and sure to be just the ticket when you're looking to shape your set lighting jussssst right, these mount easily in a standard 2.5" grip head.
Some people also call them eyebrows. I asked them about that, and their response was "We don't care what you call us. Just make sure you call us."