Toggle pin that holds the defrost switch in the "on" position, can be used in the hazard switch as well.

If you have a BMW E30 or similar and your defrost or hazard switch won't stay on, this little pin is broken or missing. Originals are black plastic and can fall out if you're not mindful changing the light bulb in the switch.

Base is 3mm x 3mm, recommend 0.2mm nozzle and print slow