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SigmasTek  |  SKU: BW-4251

APC BACK-UPS ES BK350E1 UPS High Performance Replacement Battery 5.25 lb

13% off
New arrival
Sale price $33.99 USD Regular price $38.99
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Absorbent Glass Mat (AGM) technology for enhanced durability
High rate discharge design supports emergency power needs
Maintenance-free and spill-proof construction for safety
U.L. recognized and CE certified for guaranteed quality
1-year warranty ensures reliable, factory-fresh performance
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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 BACK-UPS ES BK350E1 Battery — Compatible with APC BACK-UPS ES BK350E1

Designed for complete compatibility with the APC BACK-UPS ES BK350E1, this replacement UPS battery delivers reliable power continuity, dependable performance, and the peace of mind you need during outages. Engineered to meet or exceed OEM SLA battery specifications, this high-performance UPS battery is an ideal swap for aging or failed cells in your BK350E1, restoring runtime and protecting connected devices with a maintenance-free, spill-proof design.

Key Specifications

  • Absorbent Glass Mat (AGM) Technology
  • High Rate Discharge Design
  • Maintenance-Free Design with Spill Proof Construction
  • U.L. Recognized and CE Certified
  • Brand New, Factory Fresh
  • 1 Year Warranty
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 7.5 Ah
  • Terminal: F2
  • Compatible Model: APC BACK-UPS ES BK350E1
  • Meets/Exceeds OEM SLA battery specifications

Benefits

This replacement UPS battery is built for durability and long life. The AGM construction provides a robust internal structure that tolerates high-rate discharge cycles while remaining maintenance-free. You get a long-lasting battery solution that resists leaks and requires no watering or periodic maintenance. As a high-performance UPS battery, it supports clean, consistent power delivery to sensitive electronics, helping prevent data loss, hardware damage, and costly downtime.

Typical applications include UPS systems (especially the APC BACK-UPS ES BK350E1), emergency power supply setups, and battery-powered tools that demand reliable spurts of energy. The high rate discharge design makes this battery suitable for sudden draws during power outages and ensures connected equipment continues to operate long enough for safe shutdowns or continued operation until power is restored.

Safety and quality certifications, including U.L. recognition and CE marking, confirm compliance with industry standards. Backed by a one-year warranty and delivered factory fresh, this replacement battery minimizes the risk inherent in older or degraded cells and restores UPS performance quickly and affordably.

Ready to restore reliable backup power to your APC BACK-UPS ES BK350E1? Purchase this high-performance, long-lasting replacement UPS battery today and get dependable protection for your equipment.

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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