Required SR66 → candidate SR60 — SR60
Reference dimensions differ. A particular holder has not been evaluated; no direct replacement is established.
- Check the holder dimensions.
Batteries / SR
SR66
Silver oxide / zinc
Cross-checked Primary batteryReviewed:
1.55 VNominal voltage
Ø 6.8 × 2.6 mmReference dimensions
Reference dimensions are not universal manufacturing tolerances. Check the actual cell and holder.
The type status describes documentary checks of core specifications, not every fact or suitability for a device.
Understanding SR66 before replacement
Identify the actual battery
SR66 is a documented Silver oxide / zinc primary cell with a nominal voltage of 1.55 V. Its reference diameter is 6.8 mm and its reference height is 2.6 mm. These are nominal reference dimensions, not a promise that every manufacturer has identical tolerances.
This dataset describes a non-rechargeable bare cell, without solder tabs or wires. A tabbed or wired assembly requires a separate fit check.
What markings identify this type?
The dataset associates 1176SO, 377, SR626W, SR626SW with SR66. The manufacturer may use a different label on the package. These references help identify the type; they do not certify the battery for a particular device.
A suffix such as W or SW describes a discharge/load variant. Preserve this requirement when choosing a replacement.
Similar dimensions in this catalogue
The following types share the same reference diameter as SR66. Their height, chemistry or voltage may differ. They are comparisons, not approved substitutes:
Commonly confused markings and sizes
The same SR66 family includes SR626W and SR626SW markings, as well as 376 and 377. In the recorded cross-references, 376 is the high-drain and 377 the low-drain label. Do not disregard that requirement.
What to check before replacing SR66
Read the original device marking, verify nominal voltage and chemistry, compare diameter and height, and check the contacts and load requirements. Same diameter, identical voltage, or a familiar brand prefix alone is not enough to establish interchangeability.
The available data contains no affirmative device-specific fit test for SR66. A missing compatibility relation means “not assessed,” not “compatible.”
How reliable are these specifications?
Core type characteristics were compared with primary material from at least two independent publishers. This does not verify all model-specific values or physical suitability.
Technical specifications
| Designation | SR66 |
|---|---|
| Chemistry | Silver oxide / zinc Cross-checked using documents from two independent publishers [Energizer] [Maxell] |
| Nominal voltage | 1.55 V (Nominal) Cross-checked using documents from two independent publishers [Energizer] [Maxell] |
| Diameter | 6.8 mm Cross-checked using documents from two independent publishers [Energizer] [Maxell] |
| Height | 2.6 mm Cross-checked using documents from two independent publishers [Energizer] [Maxell] |
| Rechargeable | No Documented source [Energizer] |
| Terminal form | Bare cell without tabs or leads Curator assessment [Energizer] |
Reference dimensions are not universal manufacturing tolerances. Check the actual cell and holder.
Other designations
These codes identify the same type family. Match the load variant, terminals and device requirements separately.
1176SO[Energizer]377EnergizerSW / low drain [Energizer]SR626WW / high drain [Maxell] [Maxell]SR626SWSW / low drain [Maxell] [Maxell]376EnergizerW / high drain [Maxell]SB-AWSeikoSW / low drain [Seiko Instruments Inc.]SB-BWSeikoW / high drain [Seiko Instruments Inc.]280-39CitizenSW / low drain [Seiko Instruments Inc.]
W and SW are different load variants. The combined 357/303 product does not make every 357 and 303 product interchangeable.
Documented brands
CitizenEnergizerMaxellSeiko
Brand presence comes from product documents or documented code mappings; current availability is not checked.
Product-specific observations
Capacity belongs to an individual product and test regime. It is not a universal value for this battery type.
Energizer 377Documented source
Current availability not checked · SW / low drain [Energizer]
| Capacity | 24 mAh (Typical) Documented source [Energizer] |
|---|---|
| Test resistance | 47,000 Ω Documented source [Energizer] |
| Cutoff voltage | 1.2 V Documented source [Energizer] |
| Test temperature | 21 °C Documented source [Energizer] |
| Test schedule | Continuous discharge Documented source [Energizer] |
| Weight | 0.42 g (Typical) Documented source [Energizer] |
| Minimum product diameter | 6.6 mm Documented source [Energizer] |
| Maximum product diameter | 6.8 mm Documented source [Energizer] |
| Minimum product height | 2.4 mm Documented source [Energizer] |
| Maximum product height | 2.6 mm Documented source [Energizer] |
Replacement limits
Device compatibility has not been verified. Dimensions alone do not prove that a battery fits or works.
Replacement evidence by category
Other markings of this technical type
1176SO · 377 SW / low drain · SR626W W / high drain · SR626SW SW / low drain · 376 W / high drain · SB-AW SW / low drain · SB-BW W / high drain · 280-39 SW / low drain
These markings resolve to this type in documented sources. The exact variant and device requirements still matter.
Conditional replacement: review requirements
No conditional cross-type relation is recorded.
Known obstacles to direct replacement
Other type pairs without a recorded assessment
This pair has not been assessed. No compatibility conclusion is available.
No automatic replacement recommendation. Device compatibility has not been verified. Dimensions alone do not prove that a battery fits or works.
Documentary limits
Historical Energizer 377/376 reports 27 mAh. The documented 377 observation is 24 mAh under different conditions; neither is a type-wide capacity.
Specification comparisons
Sources & verification
- Energizer · en-377 Documented source
Energizer SR66 product datasheet
Current availability not checked
377GL1024 · Reviewed: - Maxell · maxell-sr-lr Documented source
Silver Oxide Batteries (SR) / Alkaline Button Batteries (LR)
Current availability not checked
· Reviewed: - Maxell · maxell-crossref Documented source
Micro Battery Cross Reference and Replacement Guide
Current availability not checked
October 2017 · Reviewed: - Energizer · energizer-primary Documented source
Battery Comparison Chart: primary and rechargeable batteries
Current availability not checked
· Reviewed: - Seiko Instruments Inc. · v0210-src-sii-silver-crossref Documented source
Silver Oxide Battery CROSS-REFERENCE CHART (Watch Battery Low-Drain / High-Drain)
Current availability not checked
· Reviewed: - Energizer · en-364 Historical document
Energizer SR60 product datasheet
Current availability not checked
EBC - 4322F Page 1 of 1 · Reviewed: - Energizer · en-377-376 Historical document
Historical Energizer 377-376 datasheet
Current availability not checked
· Reviewed:
Common questions
What size is SR66?
Ø 6.8 × 2.6 mm
Can SR66 be recharged?
No. Do not charge primary cells.
Can SR66 replace another battery?
Not on the basis of size or matching names alone. Check the exact device requirements and the directed compatibility notes. This catalogue does not contain a guaranteed device-fit recommendation for SR66.
How does SR66 differ from LR66?
SR66 and LR66 have reference heights of 2.6 mm and 2.6 mm respectively, and nominal voltages of 1.55 V and 1.5 V. Their chemical systems are Silver oxide / zinc and Alkaline zinc / manganese dioxide. These comparisons do not establish a permitted replacement.
Open technical comparison: LR66
This is a technical comparison, not an equivalence or fit certificate.