Introduction Download the ARC (formerly EZ-Builder) software to access the STL files for 3-D printing a robot using the Shell-E Innovation Kit, or download them below. When you load a project, the ARC software will download the required EZ-Bits and ask if you would like to view the assembly instructions. Click through the steps to find and save the EZ-Bit STL files to your computer. In this lesson, we will demonstrate how to download the software and the STL files and how to 3-D print the chassis components for creating a robot with the Shell-E Innovation Kit.