Jeff, the filters are black and are glass. The military uses them to place over the headlights of vehicles.
This evening I put them to the test. I used an aircraft landing bulb set in a utility light, with the filters over that and taped in place. I rigged up a mount for the light and placed it on my scope.
The light illuminated ok up close, to probably 40 or 50 yards, but I was disappointed in that it did not throw the light further. I was really hoping for more, but I honestly think the issue is my scope. It's just not capable of seeing further without some really bright lights.
I still haven't found anything that will outperform those small IR lights I have been using.
