Seatback bag hook

Yet another bag-holder to hang off the car seat. It's designed for a 1/2" headrest post, which fits nicely in my wife's Mazda 5.

Printed in 3 parts; a well-calibrated printer will let you press-fit the caps on the studs with no adhesive and no sanding/scraping. If you're over-extruding or they're too tight, try expanding them in x&y a little.

The parts are designed in OnShape: copy & update!
https://cad.onshape.com/documents/03b56caf03dbcaf5754494e5/w/b9dd928c85aef91b5a233033/e/be1e56e7753fd4fc4fc2c091

Update: the thing works really well, but I think one o our guests took it apart... rather than reprint the "hook" I decided to try a single-piece design: the anchor