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SigmasTek  |  SKU: BW-4271

APC BACKUPS BK420S UPS High Performance Replacement Battery 5.25 lb

21% off
New arrival
Sale price $33.99 USD Regular price $42.99
Shipping calculated at checkout.
AGM technology delivers long-lasting, reliable power
High rate discharge supports emergency and tool use
Maintenance-free with spill-proof construction
U.L. recognized and CE certified for safety compliance
Fits APC BACKUPS BK420S model, includes 1-year warranty
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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 | 7.5 Ah

Terminal Type

F2

Replacement APC BACKUPS BK420S Battery — Compatible with APC BACKUPS BK420S

Designed for perfect compatibility with the APC BACKUPS BK420S, this replacement UPS battery delivers reliable performance, dependable emergency power, and maintenance-free operation when you need it most. Whether you are restoring backup power to a home office UPS or replacing an old SLA cell, this high-performance UPS battery meets or exceeds OEM specifications and offers the dependable uptime your APC BACKUPS BK420S requires. Built with quality materials and certified safety features, it’s an ideal long-lasting battery solution for anyone seeking a cost-effective, compatible replacement.

Key Specifications

  • Compatible Model: APC BACKUPS BK420S
  • Battery Type: Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Design: High Rate Discharge Design
  • Maintenance: Maintenance-Free Design with Spill Proof Construction
  • Safety Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 7.5 Ah
  • Terminal Type: F2
  • Primary Applications: Emergency Power Supply, Battery Powered Tools

Benefits

This replacement UPS battery is engineered for durability and long life. The Absorbent Glass Mat (AGM) construction provides a sealed, leak-proof design that resists vibration and minimizes maintenance — ensuring your UPS remains ready without frequent service. The high rate discharge design supports rapid delivery of power during outages, making this a high-performance UPS battery choice for critical devices and sensitive electronics.

As a maintenance-free and spill-proof unit, it reduces downtime and simplifies replacement tasks. The U.L. recognition and CE certification confirm that the battery meets important safety and quality standards. Backed by a 1 Year Warranty and shipped brand new and factory fresh, this long-lasting battery offers peace of mind for both home and small business environments.

Typical uses include UPS backup for home and office systems, emergency power supply for networking equipment, and powering battery-operated tools where a robust SLA is required. Its 12 Volts, 7.5 Ah capacity and F2 terminal make it a direct fit for APC BACKUPS BK420S units, ensuring quick installation and reliable operation.

Ready to restore dependable backup power? Order this replacement UPS battery for your APC BACKUPS BK420S now and enjoy a high-performance, long-lasting battery replacement backed by safety certifications and a 1 Year Warranty.

Technical Specifications

Voltage12 Volts
Amp Hours7.5 Ah
Terminal TypeF2
Length (in.)5.95
Width (in.)2.56
Height (in.)3.7
Weight (lb.)5.25

Product Highlights

  • Brand Replacement : APC BACKUPS
  • Manufacturer: SigmasTek
  • Product Type: UPS Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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