What size replacement battery do I need for a relic 2r15571

all about watch batteries

https://www.fixya.com/support/r27181038-changing_watch_batteries

Your has 2 batteries

https://www.google.com/search?q=Battery+for+a+Relic+watch+ZR55080

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It will be a standard watch battery. Take it to your local jeweler.

https://www.fixya.com/support/r27181038-changing_watch_batteries

https://www.google.com/search?q=relic+desk+top+motorcycle+clock+number+RML5002001+battery

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Take your Relic watch to a jeweler who will identify the type (not size) and may replace it.

How can you find out what size watch battery fits watch

think it might be this one sr1116sw

http://www.portablepower.net.au/Maxell-SR1116SW-366-Silver-Oxide-Watch-Battery-Pack-of-5-batterie

Thank you FixYa.
Look on the back of the watch, or in the manual. If it doesnt say the battery size you will need to take to jeweler to have them measure the compartment to see what battery is needed. Sorry but no other way to know the battery needed.
Best regards. Jewel