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SigmasTek  |  SKU: BW-9461

Orthofab/Lifestyles Fortress Wheelchair 1000FS U1 High Performance Replacement Battery

Sale price $214.25 USD Regular price $280.53
Shipping calculated at checkout.

➤ Factory fresh and brand new for reliable performance

➤ 100% compatible with Orthofab/Lifestyles Fortress Wheelchairs 1000FS U1

➤ Absorbent Glass Mat (AGM) technology for deep cycle use

➤ Valve regulated and spill-proof for safe, maintenance-free operation

➤ Includes 1-year warranty for peace of mind


📦🚀 FAST SHIPPING: Usually ships same day if ordered before 2 PM EST

⚠️ Quick Reminder

🔹 Please ensure the original battery model number is listed in our product description and that your device model number matches for compatibility.
🔹 We only supply the batteries shown in the images. Device images are provided for reference only.

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Battery Care Guide

Battery Usage and Maintenance Guidelines 🔋

Please read the following instructions carefully before using your new battery. Proper adherence will help ensure optimal performance and extended service life.

1. Cordless Phones, PDAs, and Power Tools (NiMH, NiCd, Lithium-Ion) 📱

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Operate the device until the battery reaches approximately 20% capacity.
  • Avoid premature recharging.
  • Do not allow the battery to fully discharge during the initial cycles.

Post-Conditioning

  • Recharge the battery only when necessary.
  • These batteries are capable of approximately 500 charge cycles:
  • Once daily → ~500 days
    Twice daily → ~250 days
    Note: Even a partial recharge is considered a full cycle.

2. Sealed Lead Acid (SLA) Batteries 💡

  • No conditioning required.
  • Maintain the battery in a fully charged state; avoid complete discharge.
  • Capable of 300–400 charge cycles.
  • Expected service life: 2–3 years, depending on usage conditions.

3. Laptop Batteries (Lithium-Ion) 💻

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Charge fully, then discharge to approximately 20% capacity.
  • Avoid complete discharge, as some devices may not detect a fully drained battery.

Post-Conditioning

  • Minimize frequent plugging and unplugging.
  • Allow the battery to discharge moderately at least once per month to maintain optimal performance.
  • Occasional cycling is recommended to sustain battery health.

Professional Recommendation

Adhering to these guidelines will enhance battery longevity and ensure reliable performance.

For further assistance regarding your battery or order, our customer support team is available to provide guidance.

Delivery and Shipping

Everything You Need to Know About Shipping with BatteryWeb (USA)

We know reliable delivery matters when you need power fast. Here’s how BatteryWeb makes shipping easy across the USA:

🚚 Shipping & Delivery

Most orders ship next business day (some products like sealed lead acid may take a little longer).

Same-day shipping available if you order before 11:59 AM (delivery depends on the carrier).

We ship nationwide using FedEx, UPS, USPS, DHL, and regional ground carriers.

Shipping costs are calculated automatically at checkout based on weight, distance, and carrier.

Transit times shown are estimates only (business days, no weekends/holidays).

🌍 Shipping Restrictions

Lithium batteries cannot be shipped by USPS or air. They must go via FedEx Ground, UPS Ground, or DHL Ground.

PO Box deliveries are only available via USPS.

At this time, we do not ship lithium batteries to Puerto Rico. NiMH, NiCd, and Alkaline can be shipped.

📦 Important Notes

Double-check your shipping address! If an incorrect address is used and the order is returned, re-shipping costs are the buyer’s responsibility.

If a product is temporarily out of stock, we’ll notify you right away with the expected restock date—or issue a refund if you prefer.

💲 Currency & Pricing

All prices are shown in USD.

Orders shipped outside the USA may be subject to local taxes, customs fees, or import duties. These are the buyer’s responsibility.

⚡ At BatteryWeb, we’re committed to getting your batteries delivered quickly, safely, and affordably—so you’ll always have the power you need, when you need it.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

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

🔹 Our products are generic replacement parts and are not affiliated with, endorsed by, or manufactured by the original equipment manufacturers (OEMs).


Volts & Amps

12 Volts | 35 AH

Terminal Type

Nut & Bolt

Replacement Orthofab/Lifestyles Fortress Wheelchairs 1000FS U1 Battery - SP12-35 NB (12V 35AH)

Upgrade your Orthofab/Lifestyles Fortress Wheelchairs 1000FS U1 with this factory-fresh SP12-35 NB replacement battery. Engineered for compatibility and dependable performance, this long-lasting battery gives your 1000FS U1 the reliable power boost it needs. As a high-performance battery option, it provides consistent energy and durability for everyday mobility and heavier-duty applications.

Key Specifications

  • Compatible Model: Orthofab/Lifestyles Fortress Wheelchairs 1000FS U1
  • Battery Model: SP12-35 NB
  • Voltage: 12 Volts
  • Capacity: 35 AH
  • Terminal Type: Nut & Bolt (NB)
  • Technology: Absorbent Glass Mat (AGM)
  • Designed For: Deep Cycle Usage
  • Construction: Valve Regulated, Spill Proof
  • Energy: Power/Volume Ratio Yielding Unrivaled Energy Density
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Performance: Performance Guaranteed
  • Brand: SigmasTek
  • Warranty: 1 Year Warranty
  • Notes: Requires reuse of existing cables and hardware from original configuration; unit requires 2 batteries

Benefits

This SP12-35 NB replacement battery combines robust construction with AGM technology to deliver excellent cycle life and reliable output. The valve-regulated, spill-proof design increases safety and reduces maintenance, making it ideal for mobility equipment. As a high-performance battery, it supports the power demands of electric wheelchairs and mobility devices while offering the stability and endurance expected from a long-lasting battery.

The superior power-to-volume ratio and certified manufacturing provide dependable energy density so your 1000FS U1 remains responsive and efficient throughout its duty cycles. The battery’s deep cycle capability ensures it can withstand frequent discharges and recharges, which is essential for users who rely on their wheelchair for daily mobility.

Common applications include electric wheelchairs, power chairs, mobility chairs, and mobility scooters. Because the Fortress Wheelchairs 1000FS U1 requires two SP12-35 NB batteries, these units are intended to function together to deliver balanced performance and extended runtime for everyday use.

Replace your worn battery today—purchase the Orthofab/Lifestyles Fortress Wheelchairs 1000FS U1 SP12-35 NB replacement battery for a high-performance, long-lasting battery backed by a 1 year warranty. Order now to restore reliable mobility and enjoy fast shipping.


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