This is a computationally optimized shelf bracket, designed around ~100lb (~440N) loads, although I'm fairly optimistic it can hold more than this. When printed vertically, it uses no support material. 

It is incredibly strong for its weight, and the version I printed in PA612-CF30 (Fiberon) only weighs 80 grams. Even in PLA I believe this shelf bracket will perform well.

Note that triangular infill is best for an application like this as it is more rigid than other infill patterns.

Enjoy, and don't forget to post your makes!

UPDATE - 3/26/2026: Just wanted to post an update here, my shelves have stood the test of time! I will warn however, i did need to reprint the nylon version as i did not anneal the part. This made it slowly creep over time. The PLA shelf however, has not needed a replacement.