This is a 2 piece hook to install in your car's trunk so you can hook open bags so they don't move around and spill their contents in the trunk while you're driving. Perfect for grocery bags.
It is designed to fit in an existing circular 20mm diameter hole in the stamped metal that forms the ceiling of the trunk. The car I made this for is a Subaru. Your car might not have these holes or might have different sized holes depending on the make and model so it is possible that this will not fit your car or might require some part scaling adjustment to properly fit.
Installation instructions: Slide the printed hook into the printed base and insert them both into an existing hole in the ceiling of your trunk while squeezing the hook base to a smaller diameter. Once inserted, pulling down on the hook will force the hook base to expand and lock it in place. To remove you must first lift the hook through the base so the base can be squeezed again.
I screwed up the orientation when I made these parts. Both parts will have to be rotated to properly sit on the printing bed. The "ball" at the top of the hook has a flat side to better sit on the printer bed.