These mounting beams rotate and target your LED strips 40 degrees towards the build platform, giving you better illumination angle. Attach the endpieces to the main beam with an adhesive, this will provide the main beam with an extension and ziptie groves. The little notches on the side provide spacing between left/right walls and the mounting beam for the corner wires to pass through. Secure the LED strips with zipties for extra security. Mount the beams with your favorite adhesive or self tapping screws.