This is a small bracket that takes a 23mm diameter addressable LED board and mounts it a good distance (12mm or so) from a 40mm diameter disc of black LED acrylic for a very nice glowing eye effect. It has holes around the edges so it can be sewn to a mask. 

I'm driving it with an Adafruit Mini Sparkle Motion so I can power it from a USB battery pack and use the mic for sound-reactive eyes that glow when you talk.