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SigmasTek  |  SKU: BW-4217

APC BACK-UPS PRO BP420S UPS High Performance Replacement Battery

Sale price $16.99 USD Regular price $24.15
Shipping calculated at checkout.

➤ Compatible replacement for APC BACK-UPS PRO BP420S model

➤ Uses Absorbent Glass Mat (AGM) technology for reliable performance

➤ Maintenance-free and spill-proof design for hassle-free use

➤ U.L. Recognized and CE Certified for safety and quality assurance

➤ Includes 1-year warranty and factory-fresh brand new battery


📦🚀 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 | 7.5 Ah

Terminal Type

F2

Replacement APC BACK-UPS PRO BP420S Uninterruptible Power Supply (UPS) Battery

Specifically crafted for the APC BACK-UPS PRO BP420S model, this replacement UPS battery offers reliable compatibility and robust performance to keep your critical devices protected. Meeting or exceeding OEM SLA specifications, the battery is optimized for steady power delivery and dependable emergency operation. If you need a high-performance UPS battery that restores runtime and reliability, this long-lasting battery is an excellent choice for home offices, small business UPS systems, and emergency power setups.

Key Specifications

  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 7.5 Ah
  • Terminal: F2
  • Compatibility: APC BACK-UPS PRO BP420S
  • Battery Type: Sealed Lead Acid (SLA) with Absorbent Glass Mat (AGM) Technology
  • Design: High Rate Discharge Design
  • Maintenance: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty

Benefits

  • Durability: Constructed using AGM technology for rugged, leak-resistant performance that keeps your UPS operating reliably under load.
  • Long Life: The high rate discharge capability helps the battery deliver fast, reliable current while preserving overall lifespan—making it a true long-lasting battery replacement for your UPS.
  • High Performance: This replacement UPS battery provides consistent voltage output and dependable performance for sensitive electronics such as routers, modems, computers, and more.
  • Maintenance-Free Operation: Designed to be maintenance-free and spill-proof so you can install it quickly and focus on mission-critical tasks rather than routine battery upkeep.
  • Certified Safety: U.L. and CE certifications indicate adherence to recognized safety and manufacturing standards for trusted performance.
  • Typical Applications: Perfect for UPS backup, emergency power supply, battery-powered tools, small business network equipment, and home IT systems that rely on uninterrupted power.

Don't wait until a power event disrupts your work. Replace your UPS battery now with this trusted, high-performance UPS battery compatible with APC BACK-UPS PRO BP420S and restore reliable backup power—order today and enjoy fast shipping and a 1 year warranty.


Payment & Security

Payment methods

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