Punch in your secret key into this numeric matrix keypad. This keypad has 12 buttons, arranged in a telephone-line 3×4 grid. It\’s made of a thin, flexible membrane material with an adhesive backing (just remove the paper) so you can attach it to nearly anything. The keys are connected into a matrix, so you only need 7 microcontroller pins (3-columns and 4-rows) to scan through the pad. Check the tutorials tab for links to an Arduino library and example code. We include a 7-pin extra-long header strip so you can plug this into a breadboard with ease. Check out our detailed guide with wiring diagrams, libraries and example sketches for all sorts of matrix keypads. Technical Details Weight: 7.5 grams Keypad dimensions: 70mm x 77mm x 1mm (2.75\” x 3\” x 0.035\”) Length of cable + connector: 85mm 7-pin 0.1\” pitch connector Check out our detailed guide with wiring diagrams, libraries and example sketches for all sorts of matrix keypads.