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SigmasTek  |  SKU: BW-3781

Deltec RS21 UPS High Performance Replacement Battery Set 52.55 lb

18% off
New arrival
Sale price $246.99 USD Regular price $301.99
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Includes 10 SigmasTek SP12-7.5HR batteries (12V 7.5AH) for Deltec RS21 UPS
High rate discharge design for superior short-term power output
Valve regulated, spill-proof, and vibration resistant construction
Brand new, factory fresh with 1-year warranty and certified safety standards
Compatible with original cables and hardware for easy installation
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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.

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Volts & Amps

12 Volts | 7.5 Ah

Terminal Type

F2

SigmasTek SP12-7.5HR Replacement Battery Set for Deltec RS21 UPS

Restore reliable runtime to your Deltec RS21 with this brand new replacement UPS battery set engineered for performance, safety, and consistent power delivery. Designed to meet or exceed OEM expectations, these SigmasTek SP12-7.5HR batteries deliver dependable support for high-rate discharge scenarios and short-duration, high-power demands. If you need a replacement UPS battery that balances immediate output and long-term reliability for your Deltec RS21, this kit is an excellent choice.

Key Specifications

  • Battery model: SigmasTek SP12-7.5HR
  • Voltage: 12 Volts
  • Capacity: 7.5 AH
  • Quantity: 10 batteries included
  • Terminal type: F2
  • Design: High Rate Discharge Design
  • Construction: Valve Regulated Spill Proof Construction
  • Self-discharge: Low Self-discharge
  • Vibration resistance: High Vibration Resistance
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Compatibility note: Use all existing cables and hardware from original configuration to connect new UPS batteries

Benefits

These replacement UPS battery modules are built for durability and consistent performance. The high rate discharge design provides the power needed for brief but demanding loads, making this a high-performance UPS battery solution ideal for protecting critical equipment. Valve regulated, spill proof construction and low self-discharge characteristics extend shelf life and reduce maintenance concerns, while high vibration resistance helps ensure stable operation in rack or portable installations.

You’ll get a long-lasting battery option that is brand new and factory tested to meet or exceed OEM specs for the Deltec RS21. The U.L. recognition and CE certification reflect industry-standard safety and quality checks, so you can install with confidence. This set is particularly well suited to Uninterruptible Power Supply (UPS) units, emergency power supply systems, and battery powered tools that require reliable short-term, high-current support. Whether replacing end-of-life cells or building a serviceable spare, these batteries are optimized for practical field use and quick replacement.

For installation: please note you must reuse all original cables and mounting hardware from your Deltec RS21 to connect these replacement batteries. Our technically savvy staff personally tests each battery set, guaranteeing consistent performance and compatibility.

Buy this replacement UPS battery set for your Deltec RS21 now to regain reliable runtime and protect your equipment with a high-performance, long-lasting battery solution. Order today and take advantage of fast shipping and a 1 year warranty.

Technical Specifications

Voltage12 Volts
Amp Hours7.5 Ah
Terminal TypeF2
Length (in.)5.95
Width (in.)2.56
Height (in.)3.7
Weight (lb.)52.5

Product Highlights

  • Brand Replacement : Deltec RS21
  • Manufacturer: SigmasTek
  • Product Type: UPS Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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