3386 - Adafruit PiRTC - PCF8523 Real Time Clock
This is a great battery-backed real time clock (RTC) that allows your Raspberry Pi project to keep track of time if the power is lost. Perfect for data-logging, clock-building, time-stamping, timers and alarms, etc. Equipped with PCF8523 RTC, it works great with the Raspberry Pi and has native kernel support.
Works perfectly with any Raspberry Pi (or similar single board linux computer) including the Pi 1, Pi 2, Pi 3, Pi Zero, A+, B+, Pi 4, etc.
Fully assembled & tested PCB plugs directly into your Pi's GPIO pins - No soldering required!
Will keep time for 5 years or more