Punch in your secret key (or Jenny's number) into this numeric matrix keypad. This keypad has 16 buttons, arranged in a telephone-line 4x4 grid. The keys are connected into a matrix, so you only need 8 microcontroller pins (4-columns and 4-rows) to scan through the pad. Check the tutorials tab for links to an Arduino library and example code.
We include some header so you can plug this into a breadboard with ease, some light soldering is required to attach it. Or you can use plain wires if you like.
There's a great Matrix Keypad Arduino library that should work great with this item with minor adjustments. It's basically a sturdier version of our Membrane 3x4 Matrix Keypad. Starting from the left there are four row pins, and then to the right are the four column pins.
If you dig our demo, check out the Adafruit FeatherWing OLED - 128x32 OLED