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SigmasTek  |  SKU: BW-5368

Best Technologies LI 1420 (Fortress II) UPS High Performance Replacement Battery 12.66 lb

14% off
New arrival
Sale price $55.99 USD Regular price $64.99
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AGM technology for reliable and consistent UPS performance
High rate discharge design supports high power output
Maintenance-free with spill proof construction for safety
U.L. Recognized and CE Certified for trusted quality
Brand new with 1 year warranty included
In stock

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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 | 18 Ah

Terminal Type

Nut & Bolt

Replacement SigmasTek 12V 18Ah for Best Technologies LI 1420 (Fortress II)

Specifically compatible with the Best Technologies LI 1420 (Fortress II), this replacement UPS battery is built to meet or exceed OEM SLA specifications and deliver dependable standby power. Featuring Absorbent Glass Mat (AGM) technology and a maintenance-free, spillproof design, this long-lasting battery is an excellent replacement UPS battery for environments that require consistent, safe, and reliable backup power.

Key Specifications

  • Compatible UPS model: Best Technologies LI 1420 (Fortress II)
  • Battery type: Sealed Lead Acid (SLA) with Absorbent Glass Mat (AGM) Technology
  • Voltage: 12 Volts
  • Capacity: 18 Ah
  • Terminal type: Nut & Bolt
  • Brand: SigmasTek / Best Technologies compatible replacement
  • Design: High Rate Discharge
  • Maintenance: Maintenance-Free, Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year

Benefits

  • Durability and Long Life: AGM construction offers excellent resistance to vibration and deep discharge cycling, delivering a long-lasting battery solution for Best Technologies LI 1420 (Fortress II) installations. The sealed, maintenance-free design minimizes service requirements and extends service life.
  • High Performance: The high rate discharge design supports UPS applications requiring rapid energy delivery during short, high-demand events. This makes it an ideal high-performance UPS battery to safeguard sensitive electronics and infrastructure.
  • Safety and Compliance: U.L. recognized and CE certified, this replacement battery complies with industry safety standards and provides peace of mind for mission-critical deployments.
  • Versatile Use: Beyond UPS systems, this unit is suitable for emergency power supply systems and battery-powered tools that demand reliable, long-lasting battery performance.
  • Easy Replacement: With nut & bolt terminals and guaranteed compatibility, installation is straightforward for technicians and end users—restore runtime quickly and efficiently.

Don’t wait until your Best Technologies LI 1420 (Fortress II) is at risk—order this replacement UPS battery now to secure dependable backup power. With factory-fresh condition, certifications, and a one-year warranty, it’s a smart, long-lasting choice. Purchase today to ensure uninterrupted protection.

Technical Specifications

Voltage12 Volts
Amp Hours18 Ah
Terminal TypeNut & Bolt
Length (in.)7.13
Width (in.)3.0
Height (in.)6.59
Weight (lb.)12.65

Product Highlights

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

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