Watch battery · silver oxide
SR721SW (362) battery
SR721SW = 362 = SB-AK. 7.91 × 2.1 mm1 silver oxide, 1.55 V1. Equivalents: V362, B-SR58L, 601, 280-29, D362, 9916 and 5 more (14 codes in 12 code systems, full table); 27 calibres, modules and models in our base take it.
Cell types in this size
SR721SW
Low drain (SW): for plain analog watches · Silver Oxide2
13 codes in our sources name this cell type.
LR721
Alkaline cell of the same size: the IEC digits are the size, the L is the chemistry. LR721 lands on this page by that rule; our sources hold no alkaline datasheet for it, so no figures are shown.
Capacity by manufacturer
Energizer 362SR721SW
27 mAh2cutoff 1.3 V as printedDatasheet ↗
Can I use another cell instead of 362?
Verdicts follow our swap rules from the datasheet size, voltage and cell type.
Use instead of SR721SW
LR721
Fits, with a catchFits, but LR721 is alkaline and runs shorter.
Same 7.9 mm × 2.1 mm size. LR721 is an alkaline (L) cell; the watch is made for silver oxide (S). Use it to get the watch going, then fit SR721SW.
Draw both cells in the swap checkerNo: SR716SW is 0.45 mm thinner than SR721SW.
Same 7.9 mm diameter, but SR716SW is 1.65 mm against 2.1 mm: the contact spring may not reach it.
SR716SW: 7.9 mm1 × 1.65 mm1, 1.55 V1
Draw both cells in the swap checkerNo: SR726SW is 0.5 mm taller than SR721SW.
Same 7.9 mm diameter, but SR726SW stands 2.6 mm against 2.1 mm: the case back presses on it or does not close.
SR726SW: 7.9 mm1 × 2.6 mm1, 1.55 V1
Draw both cells in the swap checker
What uses 362
27 calibres, modules and models in our base name this size.
Seiko calibres27[3]
Seiko's battery chart gives 1.5–4 years of battery life for these calibres. Seiko, Pulsar, Lorus and Alba calibres share the chart.
- 5C20
- 5C21
- 5C22
- 5C23
- 5C59
- 5930
- 5931
- 5932
All 27 calibres
- 5939
- 5933
- 7424
- 7430
- 7431
- 7432
- 7433
- 7434
- 7439
- 7454
- B004
- B337
- F221
- F231
- L423
- L620
- W410
- Y661
- Y662
Questions
What is the 362 battery equivalent?
SR721SW, V362, B-SR58L, 601, 280-29, D362, 9916, 080-D22, SB-AK, SR721 and 1 more codes name the same 7.9 × 2.1 mm silver oxide cell as 362. Any maker's cell under one of these codes fits.
Is 315 the same as 362?
No. SR716SW is 0.45 mm thinner than SR721SW. Same 7.9 mm diameter, but SR716SW is 1.65 mm against 2.1 mm: the contact spring may not reach it.
Is LR721 the same as SR721SW?
No: LR721 is an alkaline cell of the same size, SR721SW is silver oxide. Fits, but LR721 is alkaline and runs shorter. Same 7.9 mm × 2.1 mm size. LR721 is an alkaline (L) cell; the watch is made for silver oxide (S). Use it to get the watch going, then fit SR721SW.
What watches use the 362 battery?
In our base: 27 Seiko calibres (5C20, 5C21, 5C22, 5C23…). The full lists are on this page, with the brand tables they come from.
How long does a 362 battery last in a watch?
Seiko's battery chart gives 1.5 to 4 years for its 27 calibres on this cell, 2 years most often. Life depends on the calibre's current draw, not on the cell alone.
Seiko battery chart[3]
Sources
Documents checked · Report a wrong number
- 1Murata — Watch Battery Selection Guide / Cross Reference · pdf · read
- 2Energizer Holdings, Inc. — Product datasheet ENERGIZER 362 · pdf · read
- 3Seiko Watch Corporation (service information) — Value Checking List / Battery No. Cross-reference Chart · pdf · read