CANADUINO® 3 x RTC Real Time Clock DS3231, 32kB Memory, I2C, Battery Backup (100% Compatible with Arduino) : Amazon.ca: Electronics
AZDelivery Real Time RTC I2C Clock Compatible with DS3231, Real Time Clock with RTC DS3231 I2C Battery, High Precision Clock Module Compatible with Arduino and Raspberry Pi Including : Amazon.com.be: Electronics
Générique - Modulo RTC (Real Time Clock) I2C, con chip DS1307 e memoria AT24C32, scheda per AVR/ARM/PIC inclusa : Amazon.it: Informatica
Amazon.co.jp: XDiscount DS1302 I2C RTC Real Time Clock Module AVR ARM PIC : Industrial & Scientific
iCSTORE DS1307 DS 1307 RTC Module I2C Real Time Digital Clock/Calendar DIY Kit, AT24C32 EEPROM 32Kb IC for Nano/UNO/PI/Single Board PC and Microcontroller, Alarm with DS18B20 Sensor Space- Pack of 1 :