For Samsung Galaxy Watch 4 Classic 42mm SM-R880N. Battery Type: Li-ion. 1.Li-Ion Laptop Battery 10.8V and 11.1V are in common use. 2.Li-Ion Laptop Battery 14.4V and 14.8V are in common use. It does NOT fit Watch4 Classic SM-R890 SM-R895 (46mm) and Watch4 SM-R870 SM-R875 SM-R875U (44mm).
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