This is a "tool" to open a siemens washing machine pump house thingy. If it is stuck with grit, it becomes very hard to open. If you use a normal hand tool, there is a good chance you will ruin the handle on the open thingy. By using this, you avoid that. You need to print it pretty solid to work, otherwise this key will snap. I used 1.6 wall thickness and 20% fill rate, 0.2 mm layer height.