This magnetic keychain connector keeps your house keys and car keys together in your pocket or purse but allows easy separation when needed. It uses readily available 1/4â? X 1/16â? Neodymium Disc Magnets embedded in the ABS during the printing process. There are two versions included; one using a single magnet and another using two magnets. The single magnet version is a bit more compact and serves a double function of serving to hold a supply of extra magnets to have with you at all times (Iâ??m constantly finding uses for these babies). The double version has a stronger magnetic field and works better if you donâ??t need to carry extra magnets. In either case, simply slice and print the corresponding stl, pausing after the pocket is formed, just before the enclosing layer. I use use the @pause feature within Repetier-Host which works beautifully. Insert the magnet(s) and resume printing. Works fine at .3mm resolution. This project was designed in FreeCAD. Iâ??ve included the FreeCAD fcstd files in case you want to make modifications. One source for the magnets is: http://www.amazon.com/gp/product/B001ANVAHI/ Enjoy! This project requires printing to the top of the pocket, pausing, adding the magnet(s), and resuming the print. I found Repetier-Host to be the most intuitive for accomplishing this so these instructions are written for that tool. If you know how to do the same thing using Pronterface or another program, please add instructions in the comments.