Features： 1、With 8 Buttons: Including 8 buttons in 2 x 4 matrix arrangement, this button key module is also a micro switch. 2、Individual Keys: All the 8 keys are independent and not influence each other, ensuring stable work performance. 3、Simpler Control: Installed on single chip microcomputer, the keypad module will largely simplify the operation. 4、Good Durability: Adopting materials, works with high efficiency, very sturdy and durable for long use. 5、Easy to Install: Comes with pin headers and installation holes, the lightweight module is very easy to install. Specification： Item Type: Button Key Module Specification: 2 x 4 matrix keyboard. Function: External expansion keyboard of single chip microcomputer. Board Size: Approx. 34 x 32mm / 1.34 x 1.26in (excluding protruding parts). Package List： 1 x Button Key Module