Feature: Support I2C protocol; With backlight power control, you can set whether to connect the backlight power through the jumper cap. Plug in the jumper cap to connect the backlight power, unplug the jumper cap to disconnect the backlight power. The contrast can be adjusted. Rotate the blue potentiometer to increase clockwise and decrease counterclockwise. The potentiometer is designed on the front, which is convenient for customers to adjust freely anytime and anywhere. Modules can be cascaded, up to 8 can be cascaded. Modify the device address by shorting A0/A1/A2. The default address is 0x27. IIC/I2C interface LCD 1602/2004 adapter board, without LCD screen. There are only 20 IO ports on the control board. Add some sensors, TF cards, etc., and there are more modules such as relays, so the IO ports are not enough. The original 1602/2004 screen needs 7 IO ports to drive, we developed this The module can save you 5 IO ports and send function library. Specification: Supply voltage: 2.5-6V Product size: 41*20*10mm/1.61*0.79*0.39" Product weight: 5g Packing size: 41*20*10mm/1.61*0.79*0.39" Gross weight: 6g Note: There may be slight size deviations due to manual measurement, different measuring methods and tools. The picture may not reflect the actual color of the item because of different photographing light, angle and display monitor. Included: 1 X Adapter Module Support I2C protocol; With backlight power control, you can set whether to connect the backlight power through the jumper cap. Plug in the jumper cap to connect the backlight power, unplug the jumper cap to disconnect the backlight power. The contrast can be adjusted. Rotate the blue potentiometer to increase clockwise and decrease counterclockwise. The potentiometer is designed on the front, which is convenient for customers to adjust freely anytime and anywhere. Modules can be cascaded, up to 8 can be cascaded. Modify the device address by shorting A0/A1/A2. The default address is 0x27. IIC/I2C interface LCD 1602/2004 adapter board, without LCD screen.