For questions, quotes, or help finding the right battery, feel free to email us at sales@batteryweb.com

New collections added! Learn more

🎉 First Order Special 🎉

First-time shoppers get 5% OFF on batteries & accessories!

WELCOME5
SigmasTek  |  SKU: BW-5678

Simplex 4005/4009/4008/4006 12V 12Ah Compatible Replacement Battery - 2 Pack

Sale price $58.43 USD Regular price $70.55
Shipping calculated at checkout.

➤ Direct replacement for Simplex 4005, 4009, 4008, and 4006 alarm systems

➤ Meets or exceeds OEM specifications for reliable performance

➤ Provides consistent and dependable power to critical safety systems

➤ Maintenance-free, sealed design for hassle-free use

➤ Includes two batteries for easy replacement and backup


📦🚀 FAST SHIPPING: Usually ships same day if ordered before 2 PM EST

⚠️ Quick Reminder

🔹 Please ensure the original battery model number is listed in our product description and that your device model number matches for compatibility.
🔹 We only supply the batteries shown in the images. Device images are provided for reference only.

📸 Send Your Battery Photo / Unsure? Expert Help

Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.
POST YOUR IMAGE

Battery Care Guide

Battery Usage and Maintenance Guidelines 🔋

Please read the following instructions carefully before using your new battery. Proper adherence will help ensure optimal performance and extended service life.

1. Cordless Phones, PDAs, and Power Tools (NiMH, NiCd, Lithium-Ion) 📱

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Operate the device until the battery reaches approximately 20% capacity.
  • Avoid premature recharging.
  • Do not allow the battery to fully discharge during the initial cycles.

Post-Conditioning

  • Recharge the battery only when necessary.
  • These batteries are capable of approximately 500 charge cycles:
  • Once daily → ~500 days
    Twice daily → ~250 days
    Note: Even a partial recharge is considered a full cycle.

2. Sealed Lead Acid (SLA) Batteries 💡

  • No conditioning required.
  • Maintain the battery in a fully charged state; avoid complete discharge.
  • Capable of 300–400 charge cycles.
  • Expected service life: 2–3 years, depending on usage conditions.

3. Laptop Batteries (Lithium-Ion) 💻

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Charge fully, then discharge to approximately 20% capacity.
  • Avoid complete discharge, as some devices may not detect a fully drained battery.

Post-Conditioning

  • Minimize frequent plugging and unplugging.
  • Allow the battery to discharge moderately at least once per month to maintain optimal performance.
  • Occasional cycling is recommended to sustain battery health.

Professional Recommendation

Adhering to these guidelines will enhance battery longevity and ensure reliable performance.

For further assistance regarding your battery or order, our customer support team is available to provide guidance.

Delivery and Shipping

Everything You Need to Know About Shipping with BatteryWeb (USA)

We know reliable delivery matters when you need power fast. Here’s how BatteryWeb makes shipping easy across the USA:

🚚 Shipping & Delivery

Most orders ship next business day (some products like sealed lead acid may take a little longer).

Same-day shipping available if you order before 11:59 AM (delivery depends on the carrier).

We ship nationwide using FedEx, UPS, USPS, DHL, and regional ground carriers.

Shipping costs are calculated automatically at checkout based on weight, distance, and carrier.

Transit times shown are estimates only (business days, no weekends/holidays).

🌍 Shipping Restrictions

Lithium batteries cannot be shipped by USPS or air. They must go via FedEx Ground, UPS Ground, or DHL Ground.

PO Box deliveries are only available via USPS.

At this time, we do not ship lithium batteries to Puerto Rico. NiMH, NiCd, and Alkaline can be shipped.

📦 Important Notes

Double-check your shipping address! If an incorrect address is used and the order is returned, re-shipping costs are the buyer’s responsibility.

If a product is temporarily out of stock, we’ll notify you right away with the expected restock date—or issue a refund if you prefer.

💲 Currency & Pricing

All prices are shown in USD.

Orders shipped outside the USA may be subject to local taxes, customs fees, or import duties. These are the buyer’s responsibility.

⚡ At BatteryWeb, we’re committed to getting your batteries delivered quickly, safely, and affordably—so you’ll always have the power you need, when you need it.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

🔹 Our products are generic replacement parts and are not affiliated with, endorsed by, or manufactured by the original equipment manufacturers (OEMs).


Volts & Amps

12 Volts | 12 Ah

Terminal Type

F2

2-Pack 12V 12Ah Replacement Battery for Simplex 4005 / 4009 / 4008 / 4006 Alarm Systems

Maintain uninterrupted protection for your Simplex alarm panels with this 2-pack of 12V 12Ah replacement batteries. Engineered as a direct replacement for Simplex models 4005, 4009, 4008, and 4006, these sealed, maintenance-free batteries meet or exceed OEM specifications to provide dependable power when it matters most. Compact, durable, and easy to install, this high-performance battery pair is perfect for both routine maintenance and emergency replacement.

Key Specifications

  • Compatible Models: Simplex 4005, 4009, 4008, 4006
  • Pack Quantity: 2-pack
  • Voltage: 12 Volts
  • Capacity: 12 Ah
  • Terminal Type: F2
  • Brand: SigmasTek
  • Battery Type: Sealed and maintenance-free
  • Meets/Exceeds: OEM specifications for reliable performance

Benefits

These replacement batteries deliver a dependable, long-lasting battery solution for Simplex alarm panels and other backup applications. The 12Ah capacity offers sufficient runtime for standard alarm functions and short-term emergency power needs. With sealed construction, these batteries require no maintenance and resist corrosion and spillage, which is especially important inside enclosed alarm cabinets.

Durability: Designed for consistent performance under load, these batteries are built to withstand the demands of daily readiness. The F2 terminal provides secure electrical connections for reliable operation and simplified replacement procedures. As a high-performance battery choice, they ensure that your alarm panels retain the power needed for signaling, notification, and monitoring during outages.

Typical applications include emergency backup for Simplex fire and security systems (models 4005, 4009, 4008, 4006), UPS units, access control systems, emergency lighting circuits, and other standby power installations. The two-pack offers convenience for scheduled maintenance cycles and provides a spare set for rapid swaps when time is critical.

Replace worn or aging cells with confidence — purchase this 2-pack of 12V 12Ah replacement batteries today to keep your Simplex systems protected and performing at their best.


Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.