Diagonal positioned bracket for 8mm by 2.25mm LED lighting strip to place in inside corners of 3D printer enclosure, to light your build area.12.5mm to a triangular side with 5mm squares that will hold a standard 8mm by 2.25mm LED thin lighting strip. These LED strips are super cheap about $5 for 5m (about 15 feet). Mine can be cut at 50mm intervals (group of 3 LEDs). This build has a combination of 50mm and 100mm lengths. I join them as needed with acetone. For my CTC printer, that's 400mm at top front, and 250mm at front sides and top sides. I solder connected short wires to join the segments. 12v power connection runs up a side from underneath. For now I use an AC brick to supply power but will soon mount a 24v dimmer switch that will run off the CTC power supply. The brackets were mounted with a couple pieces of tiny 1/4 inch slivers of 3/4 inch double sided mounting tape on one side of the bracket only (very strong tape!). The LED strips were then pushed into place in the brackets, first with one edge of the strip and then pressing the other edge into the bracket little by little (the LED strip will easily snap in with this method).