National Battery C21A High Performance Replacement Battery 7.28 lb
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National Battery C21A High Performance Replacement Battery is backordered and will ship as soon as it is back in stock.
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Battery Care Tips
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
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.
Disclaimer
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.
Volts & Amps
12 Volts | 12 Ah
Terminal Type
F2
National Battery C21A Replacement Battery — Compatible with National Battery C21A
The National Battery C21A replacement battery is engineered to be a direct, reliable substitute for the original C21A model, offering consistent power, safety certifications, and the durability expected from a high-quality sealed lead acid unit. This long-lasting battery combines AGM technology with a maintenance-free, spill-proof construction to provide dependable performance for both standby and cyclic duties. Ideal for users who need a high-performance battery that’s ready out of the box, the C21A replacement delivers proven reliability.
Key Specifications
- Compatible Model: National Battery C21A
- Battery Type: Rechargeable Sealed Lead Acid (SLA)
- Technology: Absorbent Glass Mat (AGM) Technology
- Design: Maintenance-Free with Spill Proof Construction
- Certifications: U.L. Recognized and CE Certified
- Condition: Brand New, Factory Fresh
- Warranty: 1 Year Warranty
- Replacement Brand: SigmasTek
- Voltage: 12 Volts
- Capacity: 12 Ah
- Terminal Type: F2
Benefits
The C21A replacement battery is built for durability and dependable performance. AGM construction helps extend usable life and provides stable voltage under load, while the sealed, maintenance-free design removes the need for electrolyte checks and reduces the risk of leaks during operation or transport. The combination of U.L. and CE certifications ensures compliance with recognized safety standards.
Common applications include UPS backup, emergency lighting, alarm systems, medical devices, and portable electronics that require a compact, reliable power source. This replacement battery is a great choice for those seeking a long-lasting battery that performs well in a range of environments and load profiles. Being brand new and factory fresh means it arrives ready to deliver optimal capacity from the first charge.
Backed by a one-year warranty and built as a cost-effective alternative to OEM parts, the National Battery C21A replacement offers a practical path to restore critical systems and reduce unexpected downtime.
Take action now—purchase the National Battery C21A replacement battery today to ensure uninterrupted, high-performance power and the peace of mind that comes with a new, factory-fresh unit and 1 year warranty.
Technical Specifications
Product Highlights
- Brand Replacement : National Battery C21A
- Manufacturer: SigmasTek
- Product Type: SLA Batteries
- Warranty: 12 Months
- Bulk Orders: sales@batteryweb.com
Payment & Security
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