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SigmasTek  |  SKU: BW-14576

Alexander MS521 Compatible Replacement Battery 4.08 lb

18% off
Sale price $30.99 USD Regular price $37.99
Shipping calculated at checkout.
Compatible replacement for Alexander MS521 model
Absorbent Glass Mat (AGM) technology for enhanced performance
Maintenance-free and spill-proof design for safety and convenience
U.L. recognized and CE certified for quality assurance
Brand new with a 1-year warranty for reliability and peace of mind
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Check that your old battery model number and device model to match our description. This makes sure they work together.


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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

6 Volts | 12 Ah

Terminal Type

F1

Alexander MS521 Replacement — Compatible with MS521

The Alexander MS521 replacement battery is crafted to deliver reliable, OEM-equivalent power for the MS521 model. This sealed lead acid replacement battery uses AGM technology for superior charge acceptance and stability, making it a dependable choice when uninterrupted power and long-term reliability matter. Whether you’re replacing an aging pack or stocking spare units, this replacement battery is built to provide consistent performance.

Key Specifications

  • Model: MS521 (Replacement)
  • Voltage: 6 Volts
  • Capacity: 12 Ah
  • Terminal Type: F1
  • Technology: Absorbent Glass Mat (AGM)
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Replacement Manufacturer: SigmasTek

Benefits

  • Durability: Heavy-duty AGM construction offers resistance to vibration and mechanical stress, providing dependable service life in a range of environments.
  • Long Life: The sealed SLA design reduces maintenance and supports reliable cycle performance, qualifying it as a long-lasting battery solution for many applications.
  • High Performance: Designed to meet or exceed OEM specs, this high-performance battery maintains steady voltage under load and recovers well after discharge.
  • Compliance You Can Trust: U.L. recognition and CE certification confirm adherence to established safety and manufacturing standards.
  • Typical Applications: Well-suited for UPS systems, emergency power and lighting, alarm and security systems, medical equipment, mobility aids, and power tool backups.
  • Maintenance-Free Use: Spill proof and factory sealed, this replacement battery simplifies installation and reduces the need for periodic maintenance.
  • Warranty Protection: Backed by a 1 year warranty to ensure your replacement performs as expected and to protect against early defects.

Don't wait until a failure disrupts your operations. Order the MS521 replacement battery now to secure a dependable, high-performance replacement battery that delivers long-lasting power and certified safety.

Technical Specifications

Voltage6 Volts
Amp Hours12 Ah
Terminal TypeF1
Length (in.)5.95
Width (in.)2.0
Height (in.)3.7
Weight (lb.)4.08

Product Highlights

  • Brand Replacement : Alexander MS521 Battery
  • Manufacturer: SigmasTek
  • Product Type: SLA Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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