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SigmasTek  |  SKU: BW-1550

Best Power FERRUPS FD 4.3KVA High Performance Replacement Battery Set

Sale price $366.99 USD Regular price $524.08
Shipping calculated at checkout.

➤ Set of 4 replacement batteries for Alpha Technologies CFR 5000E UPS

➤ AGM sealed battery technology for maintenance-free, leak-proof use

➤ UL certified to ensure safety and performance standards

➤ NB terminal type offers guaranteed compatibility with original set

➤ Ships quickly with a 1-year warranty for reliability


📦🚀 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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Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.
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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

Best Power FERRUPS FD 4.3KVA Replacement UPS Battery (Compatible with Best Power FERRUPS FD 4.3KVA)

Keep your Best Power FERRUPS FD 4.3KVA running at peak reliability with this complete replacement UPS battery set. These 12V 35AH batteries incorporate Absorption Glass Mat (AGM) sealed technology to provide maintenance-free, stable power for sensitive electronics and critical systems. Sourced by ReplaceUPSBattery.com and UL certified, the four-battery pack matches or exceeds original manufacturer specifications to restore your UPS to dependable operation.

Key Specifications

  • Package contains: 4 batteries (price includes all 4)
  • Chemistry: SLA (Sealed Lead Acid)
  • Battery Technology: AGM (Absorption Glass Mat)
  • Compatibility: Guaranteed compatibility with original battery set for Best Power FERRUPS FD 4.3KVA
  • Warranty: 1-year Warranty
  • Volts: 12 V
  • Amp Hours: 35 AH
  • Weight: 98.8 Lbs (as specified)
  • Length: 7.72 In
  • Width: 5.14 In
  • Height: 6.14 In
  • Terminal: NB (Nut & Bolt)
  • Brand: SigmasTek
  • Certifications: UL certified
  • Shipping Methods: UPS Ground and USPS; we ship in 1 business day for all in-stock items
  • Installation: Install in same original configuration and reuse existing cables and hardware

Benefits

  • Durability: AGM sealed batteries minimize maintenance and resist leakage, delivering dependable service in a variety of environments.
  • Long life: Built to meet or exceed OEM specifications, providing a long-lasting battery solution that preserves uptime and reliability.
  • High performance: Stable output under load protects connected equipment from disruptions and ensures smooth UPS operation.
  • Safety-first design: UL certification and SLA chemistry provide industry-standard safety and compliance for commercial and residential use.
  • Straightforward replacement: Supplied as a full four-battery pack to match the original Best Power configuration—reuse your existing connectors to simplify installation.
  • Typical applications: Ideal for UPS backup, emergency power systems, and tools or equipment that depend on steady reserve power.
  • Optimized value: Replacing the entire set maintains balanced charging and extends the useful life of your UPS battery pack.

Ready to replace your depleted batteries? Order this high-performance UPS battery set for the Best Power FERRUPS FD 4.3KVA now for fast shipping and a 1-year warranty. If you need assistance, contact our customer service team at (800) 657-1303 and we’ll help you get the right replacement UPS battery for your needs.


Payment & Security

Payment methods

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  • Discover
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  • PayPal
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  • Visa

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