This frame was designed for an 8.5 X 11" piece of glass with a .05" thickness.  I had a piece of glass that I etched with a Glowforge, but wanted to put some more light through it to make the image stand out more.    Once it was done printing, I ran my multi-colored LEDs through the gap in the middle, and the glass fit perfectly in the groove.  When I was done, I glued the corners and had part of the LED strip just slide right through the corner.  I have been very pleased with the amount of light it puts through the glass, and by printing the frame in red, it made the door look like a basketball backboard.  I have included both the Length and Width stl files where you just need to print both twice, and I also included the whole stl file.