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SigmasTek  |  SKU: BW-4781

Best Power Unity UT3K UPS Compatible Replacement Battery Set 98.89 lb

16% off
New arrival
Sale price $459.99 USD Regular price $546.99
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Includes 4 brand new SigmasTek SP12-35 NB batteries (12V 35AH)
High rate discharge design for superior UPS performance
Valve regulated, spill-proof construction for safety
Low self-discharge ensures long shelf life
U.L. recognized, CE certified, with 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.

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Volts & Amps

12 Volts | 35 AH

Terminal Type

Nut & Bolt

Replacement Battery Set for Best Power Unity UT3K UPS

Upgrade your Best Power Unity UT3K Uninterruptible Power Supply with a reliable, high-performance replacement UPS battery set designed for compatibility, consistent performance, and dependable reliability. This complete set includes four SigmasTek SP12-35 NB batteries and is engineered for high rate discharge applications where brief, high power output is required. Whether you operate critical IT equipment, medical devices, or emergency power systems, these factory-fresh batteries deliver the power and peace of mind you expect from a long-lasting battery solution. Please note: you must reuse all existing cables and hardware from your original configuration to connect the new UPS batteries.

Key Specifications

  • Battery model: SigmasTek SP12-35 NB
  • Quantity: 4 batteries per set
  • Voltage: 12 Volts
  • Capacity: 35 AH
  • Terminal type: Nut & Bolt
  • 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
  • Compatible UPS model: Best Power Unity UT3K
  • Brand: SigmasTek

Benefits

  • Durability and Safety: The valve regulated spill proof construction and high vibration resistance make these batteries a durable choice for rack-mounted and tower UPS systems, reducing maintenance needs and increasing uptime.
  • Designed for Performance: The high rate discharge design supports short bursts of higher power output—ideal for protecting sensitive loads when utility power fails—making this a true high-performance UPS battery option for the Best Power Unity UT3K.
  • Reliable Long Life: Low self-discharge characteristics and quality-controlled manufacturing produce consistent capacity over time, delivering a long-lasting battery lifecyle that you can count on during critical events.
  • Certified Quality: U.L. recognition and CE certification demonstrate that these replacement UPS battery units meet stringent safety and performance standards commonly required in commercial and industrial environments.
  • Versatile Applications: Perfect for Uninterruptible Power Supply (UPS) units, emergency power supply systems, and battery-powered tools—these batteries are built for both everyday backup and demanding power events.
  • OEM-Level Fit and Performance: Our technically savvy staff tests each battery set to ensure it meets or exceeds OEM specifications for the Best Power Unity UT3K, giving you confidence in compatibility and performance.
  • Easy Ordering and Fast Shipping: In-stock orders typically ship within 24 hours so you can replace your UPS batteries quickly and restore full backup capacity without extended downtime.

If you’re ready to replace the batteries in your Best Power Unity UT3K, choose this trusted, high-quality SigmasTek SP12-35 NB set for dependable emergency runtime and performance. Buy this replacement UPS battery set today and secure a high-performance UPS battery and long-lasting battery solution for your critical equipment.

Technical Specifications

Voltage12 Volts
Amp Hours35 AH
Terminal TypeNut & Bolt
Length (in.)7.72
Width (in.)5.14
Height (in.)6.22
Weight (lb.)98.8

Product Highlights

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

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