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SigmasTek  |  SKU: BW-1543

Best Power Unity UT4K High Performance Replacement Battery Set 98.89 lb

26% off
New arrival
Sale price $459.99 USD Regular price $619.99
Shipping calculated at checkout.
Four 12V 35AH batteries in one package for Best Power FERRUPS MX 1KVA UPS units
Maintenance-free AGM sealed lead acid chemistry for dependable power supply
UL certified for guaranteed safety and performance compliance
Compatible NB terminals allow direct swap with original batteries
Fast shipping and 1-year warranty included for reliable service
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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 | 35 AH

Terminal Type

Nut & Bolt

Best Power Unity UT4K Replacement Batteries (4 × 12V 35AH, NB) - Compatible with Best Power Unity UT4K

Replace the full battery set in your Best Power Unity UT4K with this factory-matched bundle of four replacement UPS batteries. This package includes all 4 batteries required for proper operation and is built using Absorption Glass Mat (AGM) sealed battery technology for dependable performance and safety. UL certified and designed to meet or exceed the original manufacturer specifications, these batteries provide the consistent runtime and durability expected from a high-performance UPS battery solution for the Best Power Unity UT4K.

Key Specifications

  • Compatible UPS Model: Best Power Unity UT4K
  • Volts: 12 V (each battery)
  • Amp Hours: 35 AH (each battery)
  • Terminal: NB (Nut & Bolt)
  • Chemistry: SLA (Sealed Lead Acid)
  • Technology: AGM (Absorption Glass Mat) Sealed Battery
  • Package contains: 4 batteries (price includes all 4 batteries)
  • Weight: 98.8 Lbs (set)
  • Length: 7.72 In
  • Width: 5.14 In
  • Height: 6.14 In
  • Warranty: 1-year Warranty
  • Brand / Spec Sheet Reference: SigmasTek / Best Power
  • Shipping Methods: UPS Ground and USPS (ships in 1 business day for in-stock items)
  • Guaranteed compatibility with original battery set

Benefits

  • Robust Durability: AGM construction ensures a sealed, maintenance-free battery that resists vibration and offers reliable service in demanding UPS environments.
  • Long Service Life: These long-lasting batteries are sized and specified to match the Best Power Unity UT4K, reducing the frequency of replacements and maintaining consistent backup availability.
  • High Performance: 35AH capacity per battery provides substantial runtime for equipment racks, servers, and critical infrastructure, delivering the performance expected from a high-performance UPS battery set.
  • Safe and Certified: UL certification and OEM-grade specifications give you confidence in safe operation for emergency power, telecom, and data center applications.
  • Complete Set: The package contains all 4 batteries required by the UT4K, simplifying ordering and ensuring correct match and installation.
  • Versatile Applications: Ideal for UPS backup systems, emergency power arrays, telecom cabinets, small UPS racks, and stationary power tools where a reliable multi-battery configuration is required.
  • Installation Guidance: Install the new batteries in the original configuration and reuse existing cables and hardware; verify dimensions prior to ordering if needed.
  • Support Available: Contact customer service via email, chat, or toll-free at (800) 657-1303 for assistance with fitment or technical questions.

Ensure uninterrupted protection for your Best Power Unity UT4K by ordering this complete set of replacement UPS batteries today. Fast shipping, UL certification, and a 1-year warranty make it easy to upgrade your backup power system now.

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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