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SigmasTek  |  SKU: BW-16577

FIAMM FGC21803 High Performance Compatible Replacement Battery 12.66 lb

16% off
Sale price $55.99 USD Regular price $66.99
Shipping calculated at checkout.
Compatible replacement for FIAMM FGC21803 model
Uses advanced Absorbent Glass Mat (AGM) technology
Maintenance-free with spill-proof, sealed design
U.L. recognized and CE certified for safety
Brand new with 1-year warranty for peace of mind
In stock

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Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

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


Volts & Amps

12 Volts | 18 Ah

Terminal Type

Nut & Bolt

FIAMM FGC21803 Replacement Battery — Compatible with FIAMM FGC21803

Replace your FIAMM FGC21803 with a reliable, maintenance-free alternative designed for optimal performance and compatibility. This replacement battery uses Absorbent Glass Mat (AGM) technology in a sealed lead acid (SLA) construction to deliver dependable, spill-proof operation. Ideal for customers seeking a high-performance battery and a long-lasting battery replacement, the FGC21803 unit is guaranteed compatible and competitively priced.

Key Specifications

  • Compatible Model: FIAMM FGC21803
  • Battery Type: Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM)
  • Voltage: 12 Volts
  • Capacity: 18 Ah
  • Terminal Type: Nut & Bolt
  • Replacement Brand: SigmasTek
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Design: Maintenance-Free with Spill Proof Construction
  • Warranty: 1 Year Warranty

Benefits

The FIAMM FGC21803 replacement battery provides robust, steady power with minimal maintenance. AGM technology reduces the risk of leakage and improves tolerance to vibration and shock, making this a resilient option for demanding environments. Its sealed, maintenance-free construction saves time and effort while offering safe operation in cabinets and enclosed equipment racks.

As a high-performance battery, the FGC21803 supports stable voltage output under load, which is essential for UPS systems, emergency power supplies, security and fire alarm systems, medical equipment, and a variety of portable and stationary tools. Nut & bolt terminals make connections straightforward and secure, ensuring a reliable electrical path for backup and cyclic applications. Compliance with U.L. recognition and CE certification gives added confidence in safety and manufacturing standards.

Delivered brand new and factory fresh with a 1 Year Warranty, this replacement battery is a practical option for both field replacements and planned system maintenance. If you require a long-lasting battery that matches OEM specifications and performs reliably in critical systems, this FGC21803 replacement meets those needs.

Ready to restore dependable power? Purchase the FIAMM FGC21803 replacement battery today to secure a maintenance-free, long-lasting solution for your equipment. Click to buy now and benefit from assured compatibility and reliable delivery.

Technical Specifications

Voltage12 Volts
Amp Hours18 Ah
Terminal TypeNut & Bolt
Length (in.)7.13
Width (in.)3.0
Height (in.)6.59
Weight (lb.)12.65

Product Highlights

  • Brand Replacement : FIAMM FGC21803 Battery
  • Manufacturer: SigmasTek
  • Product Type: SLA Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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