I got annoyed by that the hooks of the IKEA Hultarp kitchen organizing rail (see Ikea Screenshot) all the time fell out of the rail when taking off some things for cooking.
Therefore I printed these little locking parts. They lock into the present hole of that hook and should fit quite good (as long as Ikea didn´t change the tolerances of these parts in the past years).

If you enjoy this design and it gives you benefit in your life, consider a tiny contribution to my Paypal. It would be well appreciated. :)
--> Paypal.me/KorbiMuster