Specifications:
Display: 2-lines x 16-characters
Four Pin Definition: GND, VCC, SDA, SCL
Default I2C bus address: 0 x 3F for PCF8574AT chip, 0 x 27 for PCF8574T chip
Working voltage: 5V
Adjust Contrast: Potentiometer
Adjust Backlight: Jumper
Built-in industry standard HD44780 equivalent LCD controller.
Commonly used in: copiers, fax machines, laser printers, industrial test equipment, networking equipment such as routers and
storage devices.

Features:
1. I2C: The 1602 LCD Module with I2C port greatly enriches the human-computer interaction functions, and when they are connected to the controller, the controller without too many external ports will not occupy multiple IOs, and will not restrict other functions.
2. It has only two bidirectional data lines, a serial data line and a serial clock. How to wire: GND—GND; VCC—VCC; SDA—A4; SCL—A5
3. Widely Used: With the LCD shield, you can display whatever you want by programming the code for Raspberry Pi board. Therefore, this is a perfect choice to make your project more interesting and vivid !
4. You can adjust the contrast by the potentiometer at its back. If you don't want the backlight, you can also unplug the jumper cap at the LCD back.

Package includes:
4 x 1602 LCD Display Modules
4 x I2 C serial interface