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SigmasTek  |  SKU: BW-2439

Best Power LI 1050 (Fortress) UPS High Performance Replacement Battery Set 23.98 lb

21% off
New arrival
Sale price $89.49 USD Regular price $113.03
Shipping calculated at checkout.
Set of 4 replacement SigmasTek SP12-9HR batteries (12V 9AH)
High vibration resistance ideal for emergency power applications
Valve regulated and spill-proof for safe indoor use
Meets or exceeds OEM specs for Best Power LI 1050 (Fortress) UPS
Includes 1 year warranty with prompt shipping
In stock

— Ready to ship immediately


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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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🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.


Volts & Amps

12 Volts | 9 AH

Terminal Type

F2

Replacement Battery Set for Best Power LI 1050 (Fortress) UPS - 4 x SigmasTek SP12-9HR (12V 9AH)

Ensure uninterrupted operation of your Best Power LI 1050 (Fortress) with this premium replacement UPS battery set. The kit contains four SigmasTek SP12-9HR batteries (12 Volts, 9 AH) specifically designed for high rate discharge performance. These brand new batteries provide reliable backup and a long-lasting battery solution for critical systems. Please reuse all original cables and hardware to connect the new batteries to your LI 1050 (Fortress) UPS unit.

Key Specifications

  • Included Batteries: 4 x SigmasTek SP12-9HR
  • Voltage: 12 Volts
  • Capacity: 9 AH (Amp-hours)
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Self-discharge: Low Self-discharge
  • Durability: High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Installation Note: Use all existing cables and hardware from original configuration
  • Manufacturer/Brand: SigmasTek

Benefits

  • Trusted Backup Power: Designed to serve as a high-performance UPS battery for the Best Power LI 1050 (Fortress), this set supports critical loads during outages and peak demand intervals.
  • Robust and Safe Design: Valve regulated, spill-proof construction along with U.L. recognition and CE certification ensures safe operation and compliance with industry standards. High vibration resistance maintains integrity in demanding installations.
  • Long-Lasting Reliability: Low self-discharge extends shelf life and operational readiness, rendering this a true long-lasting battery choice that lowers long-term maintenance costs.
  • Multiple Applications: Ideal for Uninterruptible Power Supply (UPS) systems, emergency power supplies, and battery-powered tools where short bursts of enhanced power are necessary.
  • Quality Tested: Each battery set is factory fresh and tested by our technical staff to ensure performance meets or exceeds OEM requirements for your LI 1050 (Fortress).

Order your replacement UPS battery set for the Best Power LI 1050 (Fortress) today for fast shipping (most in-stock orders ship within 24 hours) and a 1 year warranty. For personalized assistance, call or e-mail our customer service team. Buy now to secure reliable, long-lasting power protection for your systems.

Technical Specifications

Voltage12 Volts
Amp Hours9 AH
Terminal TypeF2
Length (in.)5.95
Width (in.)2.56
Height (in.)3.7
Weight (lb.)23.96

Product Highlights

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

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