Battery Cross ReferenceButton cell equivalents

379 / SR521SW battery equivalent

Also sold as SR521SW. 1.55 V with a flat discharge curve — the usual choice for quartz watches.

Chemistry
Silver oxide
Voltage
1.55 V
Size
5.8 × 2.15 mm
Inches
0.228 × 0.085 in
Drain
Low drain (SW)
Typical capacity
~16 mAh
Shop 379 on Amazon See in full chart

Equivalents by brand

BrandNumber
Renata379
Energizer / Eveready379
Maxell / Panasonic / SonySR521SW
VartaV379
Rayovac379
DuracellD379
Bulova618
TimexJA
Citizen280-59
SeikoSB-AC/DC
IECSR63
IEC sizeSR521

Also known as

SR521SWV379D379618JA280-59SB-AC/DCSB-ACSB-DCSR63SR521SG0AG0

What it fits

Small analog watches. Confirm the printed number or measure the old cell before you buy — a 0.5 mm height difference will not seat correctly.

IEC names encode chemistry and size. SR is silver oxide, LR is alkaline, and CR is 3 V lithium. The digits are diameter and height in tenths of a millimeter, so SR521SW is about 5.8 mm across and 2.15 mm thick.

FAQ

What battery replaces a 379?

Any of these are common equivalents: 379, SR521SW, V379, D379, 618, JA, 280-59, SB-AC/DC. They are 1.55 V silver oxide cells, 5.8 × 2.15 mm.

Is 379 the same as SR521SW?

Yes — SR521SW is the IEC / Japanese-brand name for the same 379 cell.

What devices use a 379?

Small analog watches