However, there are a couple of things you might be referring to:
* The coin slot: This is where you insert your money. It's typically a small, rectangular opening on the front of the machine.
* The gumball dispenser: This is where the gumballs come out. It's usually a round, clear opening on the front of the machine. There may be a small lever or button near the dispenser that you push to release a gumball.
* The viewing window: Some gumball machines have a clear window on the front so you can see the different types of gumballs inside.
If you're thinking of something else, please clarify your question and I'll try to help!