Hello! Years ago I purchased an Ozark Trail multitool at Wal-Mart; while the multitool has served me well, and continues to serve me well, the fabric holster has not. The fabric belt loop ripped out of the back and I don't quite know how to repair it as there is a layer of plastic in between some fabric. So, I designed a hard plastic holster.
 

My requirements were as follows:

1. Fits on my belt, 35.5 mm high, 5 mm thick;
2. Can retain the tool when upside down and in motion;
3. Allows me to retrieve and replace the tool with one hand.

This is what I designed! Prints vertical with supports BLOCKED on the inside, and regular supports in the belt loop. I'm sure tree supports would work fine. I printed this in PETG with four walls and 35% infill. 

I did shake it upside down and while the tool rattles a bit it doesn't fall out but remains easy to remove with one hand.