This model was designed to cover the exposed PSU (Power Supply Unit) connections. It is used in the Artifex 3D Printer (http://www.3dmakerworld.com/artifex), and can be used in many 12V/24V PSU models as well. Installation instruction is provided in the Artifex Build Instruction: http://www.3dmakerworld.com/support/documents. The model was designed in Alibre (now Geomagic), and the source files can be found here: https://github.com/3dmakerworld/artifex.