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SigmasTek  |  SKU: BW-15446

Union Battery MX-12040 Premium Replacement Battery 3.5 lb

14% off
Sale price $29.99 USD Regular price $34.99
Shipping calculated at checkout.
Absorbent Glass Mat (AGM) technology for enhanced performance
Maintenance-free and spill-proof design for worry-free use
U.L. Recognized and CE Certified for safety and reliability
Brand new and factory fresh to ensure long-lasting power
1 year warranty guarantees quality and customer satisfaction
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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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⚠️ 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.


Volts & Amps

12 Volts | 5 AH

Terminal Type

F1

Union Battery MX-12040 Replacement Battery — Compatible with Union Battery MX-12040

Replace and restore power to your Union Battery MX-12040 with this direct-fit replacement battery engineered for reliability and performance. This unit offers the sealed AGM construction and maintenance-free convenience you need in critical applications. If you want a high-performance battery that provides consistent output and a long-lasting battery life, the Union Battery MX-12040 replacement is built to meet those expectations and match OEM specifications.

Key Specifications

  • Compatible Model: Union Battery MX-12040
  • Battery Type: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM)
  • Voltage: 12 Volts
  • Capacity: 5 AH
  • Terminal Type: F1
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Brand: SigmasTek
  • Warranty: 1 Year Warranty
  • Meets or exceeds OEM SLA battery specifications

Benefits

Featuring AGM design and a sealed, maintenance-free build, the MX-12040 replacement battery delivers reliable charge retention and safe, spill-proof operation. Its construction reduces the need for routine servicing while improving tolerance to vibration and shock compared with traditional flooded batteries. As a high-performance battery, it supports stable voltage delivery during discharge and is suitable for both standby and cyclic applications.

Built to last, this long-lasting battery benefits from UL recognition and CE certification to ensure it meets recognized safety and quality benchmarks. The compact SigmasTek 12V 5AH format provides a practical balance of size and capacity for many devices, and the F1 terminal supports easy installation in compatible housings. With a 1-year warranty, you receive product protection and the confidence to rely on this unit in critical situations.

Common applications include uninterruptible power supplies (UPS), emergency lighting and exit signs, alarm and security systems, medical equipment, and portable tools that demand dependable backup power. The maintenance-free, spill-proof design also makes it ideal for enclosed equipment or mobile installations where long-term reliability is essential.

Need dependable backup power? Add the Union Battery MX-12040 replacement battery to your cart today and benefit from a high-performance battery solution that’s built to last and backed by a 1-year warranty.

Technical Specifications

Voltage12 Volts
Amp Hours5 AH
Terminal TypeF1
Length (in.)3.54
Width (in.)2.76
Height (in.)3.98
Weight (lb.)3.5

Product Highlights

  • Brand Replacement : Union Battery MX-12040
  • Manufacturer: SigmasTek
  • Product Type: SLA Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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