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Silver-oxide watch (SR)

SR936SW battery: equivalents & specs

The SR936SW, retail number 394, is a 1.55 volt silver-oxide battery measuring 9.5 mm across and 3.6 mm tall, with a substantial 67 to 70 mAh. It is the tallest common cell in the 9.5 mm watch family, above the 373, 371 and 395.

SR936SW battery drawing: 9.5 mm across, 3.6 mm thick SR936SW 1.55V + ⌀ 9.5 mm 3.6 mm
SR936SW, face and side profile, drawn to scale: 9.5 mm across, 3.6 mm thick.
Voltage
1.55 V
Size (D×H)
9.5 × 3.6 mm
Chemistry
Silver oxide (Ag2O)
Capacity
67-70 mAh

Same battery, other names

Every code below is the exact same cell as SR936SW. Any of them will fit and work identically.

394SR45V394SR936W (380, high drain)

Compatible replacements

  • LR936 / AG9: Alkaline same-size cell with lower capacity; acceptable in toys only.

Buying and replacement notes

The 394's height gives it nearly double the capacity of the everyday 371, which is why larger movements and long-life designs specify it. The 380 (SR936W) is the high-drain version in the same case. The usual family warning applies: four cells share this diameter, so match the code, not the look.

Commonly used in

analog watcheslarger quartz movementsinstruments

Need a replacement?

Shop SR936SW batteries on Amazon →

Comparisons

LR936 vs SR936

⚠️ Keep away from children. Swallowed button batteries, especially 20 mm lithium coins, cause severe injury within hours. If a child swallows one, call the 24/7 National Battery Ingestion Hotline (US) at 800-498-8666 or poison control at 800-222-1222 immediately. What every parent should know.

Frequently asked questions

What is a 394 battery equivalent to?
The 394 is the SR936SW: 1.55 V silver oxide, 9.5 mm across, 3.6 mm tall, around 68 mAh. The 380 (SR936W) is its high-drain twin in the identical case. The alkaline AG9/LR936 fits the same slot with roughly 20 percent less capacity.
Can I put a 394 in a watch that takes a 371?
No. The 394 is 3.6 mm tall against the 371's 2.05 mm; the case back will not close. Capacity never justifies forcing a taller cell. If you want longer life in a 371 watch, buy a fresh, genuine low-drain 371 and nothing else.
How long does a 394 last?
Three years or more in many analog movements, because its capacity is large relative to a watch's microamp draw. In instruments or feature watches using the high-drain 380, life depends heavily on how often the high-current functions run.

More Silver-oxide watch (SR) cells

SR416SWSR512SWSR516SWSR521SWSR527SWSR616SWSR621SWSR626SWSR716SWSR721SW