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SigmasTek  |  SKU: BW-16677

Union Battery MX-12120 High Performance Replacement

Sale price $25.99 USD Regular price $38.61
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 long life

➤ 1 Year Warranty provides peace of mind and protection


📦🚀 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.

📸 Send Your Battery Photo / Unsure? Expert Help

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 | 12 Ah

Terminal Type

F2

Union Battery MX-12120 Replacement Battery — Compatible with Union Battery MX-12120

For dependable power in your Union Battery MX-12120 device, choose this engineered replacement battery that meets OEM SLA specifications. The Union Battery MX-12120 replacement features Absorbent Glass Mat (AGM) technology in a sealed, maintenance-free design to deliver reliable performance under steady loads and during emergency use. This factory-fresh unit is ready to install and provides consistent, long-term power for a wide range of applications.

Key Specifications

  • Model: Union Battery MX-12120
  • Battery Type: Rechargeable Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM)
  • Voltage: 12 Volts
  • Capacity: 12 Ah
  • Terminal: F2
  • Design: Maintenance-Free, Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Replacement Brand: SigmasTek

Benefits

  • Durability: The AGM design and sealed build resist vibration and environmental factors, providing reliable service life as a replacement battery.
  • Long life: Engineered for extended cycle life, this long-lasting battery reduces maintenance frequency and cost over time.
  • High performance: Stable voltage under load and excellent charge acceptance make it a solid choice for both standby and cyclic applications.
  • Maintenance-free convenience: Spill-proof construction eliminates the need for electrolyte checks or top-ups, simplifying deployment.
  • Compliance and safety: U.L. recognized and CE certified for added assurance in commercial and residential installations.
  • Typical applications: Well-suited for UPS units, emergency lighting, security systems, point-of-sale hardware, medical devices, and portable power tools that require a dependable 12V supply.
  • Easy swap: Built to be fully compatible with the Union Battery MX-12120 model for a quick and reliable replacement.

Restore reliable power with this Union Battery MX-12120 replacement battery. If you want a high-performance battery that’s long-lasting and ready to go out of the box, order now and take advantage of fast shipping and a 1 year warranty for peace of mind.


Payment & Security

Payment methods

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