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SigmasTek  |  SKU: BW-9767

Fortress Scientific 2000FS U1 Wheelchair High-Performance Replacement Battery 49.45 lb

19% off
New arrival
Sale price $245.99 USD Regular price $304.99
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Factory fresh and brand new for reliable performance
100% compatible with Fortress Scientific 2000FS U1 wheelchair units
Absorbent Glass Mat (AGM) technology for deep cycle use
Valve regulated, spill-proof design for safety and durability
U.L. recognized, CE certified, and backed by a 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.

Delivery and Shipping

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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

Replacement Fortress Scientific 2000FS U1 Battery (SP12-35 NB)

This factory-fresh replacement battery is 100% compatible with the Fortress Scientific 2000FS U1 wheelchair and delivers reliable performance and dependable power when you need it most. Designed and packed to the original equipment specifications, this Fortress Scientific 2000FS U1 replacement battery offers deep-cycle capability, exceptional energy density, and spill-proof safety features — making it an excellent high-performance battery option for mobility devices. If you rely on your wheelchair for daily independence, this long-lasting battery replacement restores runtime and confidence while maintaining the original connector and mounting requirements.

Key Specifications

  • Compatible Model: Fortress Scientific 2000FS U1
  • Replacement Model: SP12-35 NB (12 V 35 AH)
  • Voltage: 12 Volts
  • Capacity: 35 AH
  • Terminal Type: Nut & Bolt
  • Brand: SigmasTek
  • Battery Technology: Absorbent Glass Mat (AGM)
  • Design: Designed for Deep Cycle Usage
  • Construction: Valve Regulated Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Quantity Required: 2 batteries for the Fortress Scientific 2000FS U1
  • Installation Note: Use all existing cables and hardware from original configuration

Benefits

  • Durability: AGM construction and valve-regulated design protect internal plates and prevent leaks, delivering a rugged, maintenance-free power source built to withstand daily use in mobility applications.
  • Long Life: Engineered for deep cycle usage, this long-lasting battery provides consistent discharge/charge cycles so your wheelchair maintains runtime over months and years of regular operation.
  • High Performance: High power-to-volume ratio yields unrivaled energy density, giving you more usable energy in a compact form factor — a true high-performance battery for tight battery bays.
  • Safety & Compliance: U.L. recognition and CE certification ensure the battery meets stringent safety and quality standards, minimizing risk in medical and mobility devices.
  • Versatile Applications: Ideal for electric wheelchairs, power chairs, mobility chairs and mobility scooters; also suitable as a dependable backup battery solution in UPS, emergency power systems, and portable tools where 12V 35AH capacity is required.
  • Easy Replacement: Fits the original SP12-35 NB specification — simply reuse your existing cables and hardware for a fast swap-out and immediate restored performance.

Ready to restore reliable mobility? Order this Fortress Scientific 2000FS U1 replacement battery (SP12-35 NB) today for a high-performance, long-lasting battery upgrade. Purchase now to secure fast shipping and a 1 year warranty for peace of mind.

Technical Specifications

Voltage12 Volts
Amp Hours35 AH
Terminal TypeNut & Bolt
Length (in.)7.72
Width (in.)5.14
Height (in.)6.22
Weight (lb.)49.4

Product Highlights

  • Brand Replacement : Fortress Scientific 2000FS
  • Manufacturer: SigmasTek
  • Product Type: Medical Equipment Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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