A simple protractor with a large diameter. 

• No additional parts (such as metal screws) required
• AMS optional
• No supports required
• Printing time less than 1 hour 

If you don't have an AMS but still want to print in two colors, pause the print after the tenth layer and change the filament. This will result in the screw and nut also being two-colored. If you don't want this, print these parts separately on a second print plate.