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SigmasTek  |  SKU: BW-4239

APC Back-UPS Pro BP420SI UPS High Performance Replacement Battery 5.25 lb

8% off
New arrival
Sale price $33.99 USD Regular price $36.99
Shipping calculated at checkout.
AGM technology for long-lasting, stable power
High rate discharge supports emergency and tool use
Maintenance-free and spill-proof for easy maintenance
U.L. recognized and CE certified for safety
Fits APC Back-UPS Pro BP420SI, backed by 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 SigmasTek 12V 7.5Ah for APC Back-UPS Pro BP420SI

Restore full backup functionality to your APC Back-UPS Pro BP420SI with this high-quality replacement UPS battery. Engineered to meet or exceed OEM SLA specifications and guaranteed compatible with the APC Back-UPS Pro BP420SI, this battery provides dependable performance, safe operation, and maintenance-free convenience. It’s an ideal choice for protecting workstations, home servers, and networking gear during power disturbances.

Key Specifications

  • Compatible Model: APC Back-UPS Pro BP420SI
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 7.5 Ah
  • Terminal Type: F2
  • Battery Type: SLA / AGM (Absorbent Glass Mat)
  • Design: High Rate Discharge Design
  • Maintenance: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Applications: Emergency Power Supply, Battery Powered Tools

Benefits

With AGM technology and a high-rate discharge profile, this replacement UPS battery is a high-performance UPS battery that offers dependable output and stable recharge behavior. The maintenance-free, spill-proof design simplifies replacement and reduces the risk of leaks or corrosion in your APC Back-UPS Pro BP420SI. U.L. recognition and CE certification further attest to the product’s safety and quality for consumer and small business applications.

This long-lasting battery performs well in UPS systems, emergency power supplies, and portable equipment. It helps preserve data integrity, maintain network uptime, and provide backup for critical peripherals. The compact 12V 7.5Ah format and F2 terminals make for an easy, secure swap that gets your Back-UPS Pro BP420SI back to full service quickly.

Choosing this brand-new, factory-fresh battery with a 1-year warranty is a practical, cost-effective way to extend the life of your UPS and ensure consistent protection from power events.

Get reliable backup power today—add this replacement UPS battery for the APC Back-UPS Pro BP420SI to your cart now and safeguard your equipment with a trusted, long-lasting solution.

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 Back-UPS
  • Manufacturer: SigmasTek
  • Product Type: UPS Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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