20Pcs I2C RTC DS1307 AT24C32 Real Time Clock Module For AVR ARM PIC SMDDescription:24C32 32K I2C EEPROM memoryUsing LIR2032 rechargeable lithium battery with charging circuitSolve the problem of no literacy of the DS1307 with backup batterySupport timing 1 year of the DS1307 after fully chargedLeads to the DS1307 clock pin provides a clock signal for the microcontrollerOther I2C devices can be cascadedSize: 27 x 28 x 8.4mmNote:Because of shipping restrictions, we won't ship batteryPackage included:20 x DS1307 module ( battery is not included )