2X2 MATRIX Keyboard Module - 4 Buttons (OT3688)

keyboard matrix is a great way to add buttons without using up all your I/O pins. This Universal Matrix Keyboard has 4 buttons in a 2x2 matrix. One side of the board includes a pin header that allows you to quickly and easily connect the keyboard to an Arduino module or other driver. Technical specifications Pitch: 2.54 4-pin connector Dimensions 20 mm x 25 mm Application examples: Front panel of any device, Combination lock, Calculator, shortcuts for your computer.