A27 (12V) Batteries

A27 batteries are narrow, 12‑volt alkaline cells designed for compact devices that need short bursts of higher voltage. You’ll commonly find them in slim remote controls (e.g., some car security fobs), wireless doorbells, garage door openers, and laser pointers where space is tight.

How to Choose the Right A27

• Confirm compatibility: Your device manual or battery compartment should list A27 or an equivalent code (see “Equivalents” below). If it specifies A23, do not substitute an A27.
• Freshness first: Prefer recent date codes/“best by” dates. Shelf life is typically 2–3 years; older stock may deliver reduced performance.
• Capacity and brand: A27 cells usually deliver about 20–30 mAh. Reputable brands often maintain voltage better under pulse loads used by remotes.
• Operating environment: For outdoor remotes, look for stated operating ranges around 14–122°F (-10–50°C).
• Pack size and cost: If you use multiple devices, multi-packs lower cost per cell. Store spares sealed in a cool, dry place.

A27 vs A23: Which Do You Need?

Both are 12 V miniature batteries, but they are not interchangeable. Devices are designed for one size or the other.

Attribute	A27	A23
Diameter × Length	≈ 8 × 28 mm	≈ 10 × 28 mm
Typical capacity	≈ 20–30 mAh	≈ 50–60 mAh
Best for	Very slim remotes and transmitters	Devices with slightly more space and runtime needs

Choose A27 if your device calls for it or has a very narrow battery bay. Choose A23 only if explicitly specified by the device.

Common Uses

• Car security and RF remotes with narrow battery compartments
• Wireless doorbells and chimes
• Garage door opener transmitters
• Laser pointers and small gadgets

Performance and Expected Runtime

• Intermittent remote use: Typically several months to a year, depending on signal strength needed and how often you press the button.
• Continuous draw estimate: At ~10 mA, expect roughly 1–2 hours of continuous runtime from a 20–30 mAh cell. High current or cold weather shortens this.
• Signs to replace: Reduced range, intermittent operation, or dim indicator LEDs.

Equivalents and Specs

These part numbers commonly refer to the same A27 size. Always confirm on your device or manual:

• A27, 27A, MN27, V27A, GP27A, LR27A, L828

Specification	Typical Value
Chemistry	Alkaline (non‑rechargeable)
Nominal voltage	12 V
Capacity	≈ 20–30 mAh (varies by brand/load)
Dimensions	≈ 8 mm diameter × 28 mm length
Operating temp	≈ 14–122°F (‑10–50°C), brand dependent

Use/Don’t Use Guidance

• Use A27 when your device explicitly calls for A27/27A and has a narrow battery bay needing 12 V bursts.
• Avoid A27 if your device specifies A23 or a 3 V coin cell (e.g., CR2032); they are not compatible.
• Do not recharge: A27 is not rechargeable. Never place in a charger.

Safety and Disposal

• Keep out of reach of children and pets; ingestion can be dangerous. Seek immediate medical attention if swallowed.
• Do not mix old and new batteries or different brands in the same device.
• Store in a cool, dry place; avoid heat, moisture, and metal-to-metal contact.
• Recycle where local programs accept alkaline batteries; avoid disposing in household trash when recycling is available.

FAQ

Are A27 and A23 interchangeable?
No. They are different diameters and capacities. Use exactly what your device specifies.

How can I tell if an A27 is fresh?
Check the date code or “best by” on the packaging. Choose the most recent stock and store spares sealed.

Why does my remote drain A27 batteries quickly?
High transmit power, frequent use, poor contacts, or cold temperatures can reduce runtime. Clean terminals and consider a reputable brand.

Are there rechargeable A27 equivalents?
No standard rechargeable A27 exists. Use only non‑rechargeable alkaline A27 recommended by the device maker.

What are the exact equivalent codes I can buy?
Look for A27, 27A, MN27, V27A, GP27A, LR27A, or L828; these typically indicate the same size.