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SigmasTek  |  SKU: BW-4258

APC Back-UPS 350 BK350EI UPS Compatible Replacement Battery 2.98 lb

19% off
New arrival
Sale price $28.99 USD Regular price $35.99
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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 | 3.5 Ah

Terminal Type

F2

Replacement APC 350 BK350EI Battery — Compatible with APC 350 BK350EI

Keep your APC 350 BK350EI operating at peak reliability with this replacement UPS battery engineered for compatibility and performance. Meeting or exceeding OEM SLA specs, this high-performance UPS battery provides dependable backup power, proven safety certifications, and the long-lasting reliability you expect for home and small business UPS systems.

Key Specifications

  • Compatibility: APC 350 BK350EI
  • Battery Type: Absorbent Glass Mat (AGM) Technology
  • Design: High Rate Discharge Design
  • Maintenance: Maintenance-Free Design with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 3.5 Ah
  • Terminal Type: F2
  • Intended Use: APC Back-UPS / Back-UPS systems

Benefits

This replacement UPS battery combines rugged construction and proven chemistry to deliver long service life and reliable operation. The AGM design and high rate discharge capability ensure consistent power delivery during outages, qualifying it as a high-performance UPS battery for sensitive electronics. Its maintenance-free, spill-proof build keeps handling and upkeep simple and safe.

Whether used for emergency power supply to protect networking gear, or in portable applications with battery powered tools, this long-lasting battery offers the stable output needed to avoid downtime. U.L. and CE certifications reinforce the unit’s safety credentials and suitability for a variety of applications.

Packaged brand new and factory fresh, this SigmasTek battery uses standard F2 terminals for straightforward installation in APC 350 BK350EI units. The included 1 year warranty and our compatibility guarantee let you replace your old battery with confidence, restoring runtime and protection for critical devices.

Ready to upgrade the backup power in your APC 350 BK350EI? Buy this replacement UPS battery now to secure a durable, high-performance, long-lasting battery and keep your systems safe during power events.

Technical Specifications

Voltage12 Volts
Amp Hours3.5 Ah
Terminal TypeF2
Length (in.)5.24
Width (in.)2.64
Height (in.)2.36
Weight (lb.)2.98

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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