Features: The DS3231SN Real Time Clock Module deliver precise timekeeping with integrated temperature compensation, ensuring minimal drift for microcontroller project. Featuring low power consumption, this I2C module supports programmable alarms, multiple time format, and diagnostics for integration into electronics. Ideal for developers, engineers, and hobbyists building devices, automation systems, or battery power projects requiring reliable real time clock functionality. Perfect for electronics, and industrial applications where accurate timestamp tracking and space efficient solution are critical. With user friendly pin headers and broad microcontroller compatibility, this DS3231SN module simplifies prototyping while maintaining in temperature variable environment. Specifications: Size:Approx.3cm/1.18inch Battery Type: CR1220 Button Battery Communication: I2C Package Includes: 2 Optional Package: Package 1 Include:1 Set Real Time Clock Module Package 2 Include:3 Set Real Time Clock Module note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual of the item.