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SigmasTek  |  SKU: BW-15997

National NB12-3.5 Long-Life Replacement Battery 2.98 lb

15% off
Sale price $28.99 USD Regular price $33.99
Shipping calculated at checkout.
Compatible replacement for National Battery NB12-3.5 model
Uses advanced Absorbent Glass Mat (AGM) technology for reliable performance
Maintenance-free and spill-proof design for hassle-free use
U.L. Recognized and CE Certified for safety and quality assurance
Comes brand new with a 1-year warranty for peace of mind
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Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

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


Volts & Amps

12 Volts | 3.5 Ah

Terminal Type

F1

National Battery NB12-3.5 Replacement Battery — Compatible with National Battery NB12-3.5

Restore dependable performance with this replacement battery for the National Battery NB12-3.5. Designed as a sealed lead acid (SLA) solution using AGM technology, this replacement battery provides safe, maintenance-free power for critical systems. Whether you need reliable backup for emergency devices or steady power for everyday tools, this high-performance battery offers the consistency and reliability you expect.

Key Specifications

  • Compatible Model: National Battery NB12-3.5
  • Replacement Brand: SigmasTek (replacement for National Battery)
  • Chemistry: Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM)
  • Voltage: 12 Volts
  • Capacity: 3.5 Ah
  • Design: Maintenance-Free, Spill Proof
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

This National Battery NB12-3.5 replacement is built to deliver long life and dependable operation. AGM construction enhances durability and reduces leakage risk, while the sealed, maintenance-free design allows installation in various orientations without concern for spills. These traits contribute to a long-lasting battery solution that minimizes upkeep and replacement frequency.

The battery is ideal for a broad range of applications including UPS systems, emergency lighting, alarm and security systems, medical devices, and portable power tools. Its steady discharge profile and reliable recharge acceptance make it a true high-performance battery for both standby and cyclic use. U.L. recognition and CE certification further validate its safety and performance credentials.

Designed to meet or exceed OEM specifications for the NB12-3.5, this replacement battery provides predictable power delivery and easy installation. The brand-new, factory-fresh condition ensures immediate readiness and longevity in service.

Ready to secure uninterrupted power? Buy this National Battery NB12-3.5 replacement battery now and enjoy a long-lasting battery backed by a 1 year warranty. Order today for reliable, high-performance backup.

Technical Specifications

Voltage12 Volts
Amp Hours3.5 Ah
Terminal TypeF1
Length (in.)5.24
Width (in.)2.64
Height (in.)2.36
Weight (lb.)2.98

Product Highlights

  • Brand Replacement : National Battery NB12-3.5
  • Manufacturer: SigmasTek
  • Product Type: SLA Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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