This is a Digital Kepad, with push buttons 0-9 set up just like a calculator number keypad, and when you press a button, it displays which number you press and holds that value until you press another button. Make sure to hold down the button for at least one full second in order to allow everything to process after the propagational gate delays.
Buttons are arranged like this: 1 2 3
4 5 6
7 8 9
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