Don't forget to add one (or more) of these to your cart if you own or are buying an XU4. At this low price it just makes sense to have the RTC battery installed. I'm not sure what other Odroid SBCs this works with but for the low price, it should be added if your SBC has the socket for this battery. With this battery installed your SBC will display the correct time and date at boot instead of waiting a few to several minutes after connecting to the Internet to sync the time. On the XU4, it fits inside every case I own.