iPad Pro 12.9in 3rd Gen magnetic desk mount

This holder uses the magnet locations from Apple's case accessory document.  Hidden in the back is a cubby for an 18650 pack to keep the iPad charged up on long sessions.  This one is a New Trent IMP120D, which appears to be discontinued.  The pocket is 29x92mm.  Finally, there is a strain relief for a USB-C cable at the right height.  Note that the battery pack is not needed to keep the CG inside the feet.  It does not wobble even without the battery pack.

Printed with 2 outer walls and 5% infill with Bambu PLA Tough.  The overhang for the cubby needs support, as does the strain relief.  The 30 degree overhang printed without support, but was nice and slow on the layer speed.

Magnets are 1/8in cubes (KJ Magnetics B222G-N52).  These are mapped according to the polarity map (see files section) and Loctite 403'd into place.  Then a thin piece of tape protects against scraping.  Note that I only installed 2 of the 4 clusters and it's plenty strong.  

When not in use, it mounts to any magnetic surface and can hold the battery pack vertically.

To move a window from your Mac to the iPad, hover the mouse over the green window button. If your iPad is on the same account and physically nearby, an option should appear to move it to the iPad. Your Mac’s mouse and keyboard will work on the window as usual. Go to settings > display to adjust the physical location of the iPad to match your desk.