Owner manual / English
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Casio Module 1271 Manual
Two owner's manual PDFs for the Casio module 1271, each a different scan (English included). Casio's spec sheet lists one BR2020, with 10 years of battery life and accuracy within ±30 seconds a month.
Module specs
Battery: BR2020 (lithium)
Rated battery life: 10 years
Rated accuracy: ±30 sec/month
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