【Clock Module With Coin Battery】The DS3231RTC is used as a real time clock chip which keeps the time running even if the main power supply is off (with the help of a battery). | 【Complete Clock Calendar】Functionality Including Seconds, Minutes, Hours, Day, Date, Month, and Year, with Leap-Year Compensation Up to Year 2100. | 【Micro SD Mini TF Card】Easy and cost-effective expansion of your Arduino storage space via this SD card module. The SD card module interface is a standard SPI interface. Easy communication with the Arduino SPI protocol. | 【LCD 128X64 display Module】With high resolution of 128 x 64 pixels, the built-in standard driver chip SSD 1306 already exists in the libraries of Arduino, Raspberry Pi and 51 Series,which makes programming very easy. | 【With 40Pin Jumper Wire】10cm 40Pin Male-to-Female Jumper Wire is included in the package, with which you can easy to connect to other modules. If you don't know how to use it, please contact us on Amazon to get the PDF tutorial.