This is a strong hook. I wanted to design a strong hook that doesn't use too much filament. I tested it up to 50 lbs in a very scientific test. 

 

It did make some concerning noises at 50 lbs so I would recommend less than 40.

I printed mine in PLA with 10% infill and 6 walls. It is meant to be printed in the orientation the model is in. At an angle for max stronk.

You will most likely need brim to keep it upright, but NO supports. I used 6mm of brim.

This is a strong hook, but please be mindful of hanging expensive things on them. I use mine for my guitars, but I also have tested mine and how my printer printed it. Your results may very.