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SigmasTek  |  SKU: BW-16842

Union MX-121000 Compatible Replacement Battery

Sale price $214.99 USD Regular price $321.34
Shipping calculated at checkout.

➤ Absorbent Glass Mat (AGM) technology for enhanced performance

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

➤ U.L. Recognized and CE Certified for safety and reliability

➤ Brand new, factory fresh condition ensures optimal lifespan

➤ 1-year warranty for peace of mind and guaranteed quality


📦🚀 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 | 100 Ah

Terminal Type

Nut & Bolt

Union Battery MX-121000 Battery (Replacement) — Compatible with Union Battery MX-121000

For a trustworthy replacement battery for your Union Battery MX-121000, choose a unit designed for compatibility and performance. This Union Battery MX-121000 replacement battery meets or exceeds OEM SLA battery specifications and provides the reliable reserve power you expect. Featuring Absorbent Glass Mat (AGM) technology and a maintenance-free, spill-proof build, this high-performance battery gives dependable operation in both standby and active roles.

Key Specifications

  • Model: Union Battery MX-121000 (replacement)
  • Type: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Voltage: 12 Volts
  • Capacity: 100 Ah
  • Terminal: Nut & Bolt
  • Design: Maintenance-Free with Spill Proof Construction
  • Safety/Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Replacement Brand: SigmasTek (replacement)
  • Compatibility: Meets or exceeds OEM SLA battery specifications for Union Battery MX-121000

Benefits

The Union Battery MX-121000 replacement battery is built for endurance and dependable operation. The AGM design improves performance in cycling and standby roles while providing enhanced vibration resistance. Its sealed, maintenance-free nature reduces upkeep and eliminates the hazards associated with open-cell batteries. As a result, you get a long-lasting battery that stays ready for extended periods of standby duty or repeated charge/discharge cycles.

This high-performance battery is suited for UPS units, emergency power systems, security and alarm panels, telecom racks, and electric tools. The nut-and-bolt terminals facilitate strong mechanical and electrical connections, minimizing voltage drop and ensuring efficient power delivery under load. U.L. and CE certifications combined with factory-fresh condition make this replacement battery a dependable and safe option for both commercial and residential installations.

Backed by a 1-year warranty, the Union Battery MX-121000 replacement battery from SigmasTek gives you confidence in performance and long-term value. It’s an ideal choice when replacing worn or failing batteries in critical systems.

Take the next step—order the Union Battery MX-121000 replacement battery now to secure a long-lasting, high-performance battery that keeps your equipment running when it counts.


Payment & Security

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