5V to 21V Boost Cable – USB DC Adapter for 21V Battery Charging
5V to 21V Boost Charging Cable – USB to DC Adapter
Keep your 21V power tool batteries topped up anywhere you have a standard 5V USB charging head. This compact boost cable steps up voltage from 5V to 21V, giving you a convenient way to charge compatible 21V batteries using a common USB power source — no proprietary charger required.
Made in Mainland China.
Key Features
- Voltage Boost: Converts 5V USB input to 21V DC output for compatible battery charging
- DC Interface: Standard DC connector for secure, stable connection to 21V battery packs
- Durable Construction: Built from high-quality plastic materials for long-lasting everyday use
- Generous Length: Approx. 73 cm (about 28.7 in) cable for flexible positioning during charging
- Universal Compatibility: Works with 21V battery packs and standard 5V USB charging heads
- Replacement Ready: Perfect replacement for damaged or worn-out charging cables
- Brand New & Unused: Supplied in original, unused condition straight from the manufacturer
Specifications
| Product Name | 5V to 21V Boost Cable |
| Material | Plastic |
| Color | Black |
| Cable Length | Approx. 73 cm (~28.7 in) |
| Input Voltage | 5V (USB) |
| Output Voltage | 21V (DC) |
| Compatibility | 21V battery packs / 5V USB charging heads |
Package Contents
- 1 × 5V to 21V Boost Cable
Notes
- Actual color may vary slightly from images due to monitor brightness and lighting conditions.
- Please allow a slight deviation (±1–2 cm) in manual measurements.
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Frequently Asked Questions
Q: What does this 5V to 21V boost cable do?
A: This boost cable steps up the voltage from a standard 5V USB power source (such as a USB wall adapter or power bank) to 21V DC output, allowing you to charge compatible 21V battery packs without a dedicated proprietary charger.
Q: Is this cable compatible with all 21V battery packs?
A: This cable is designed for use with 21V battery packs that accept a standard DC interface connector. We recommend verifying your battery pack's input connector type and specifications before purchasing to ensure compatibility.
Q: Can I use this cable with any 5V USB charger?
A: Yes — this boost cable is designed to work with standard 5V USB charging heads, including USB wall adapters and power banks. Please ensure your USB source can supply adequate current for your specific battery charging requirements.
Q: How long is the cable?
A: The cable measures approximately 73 cm (about 28.7 inches) in length, giving you flexible reach during charging sessions.
Production & Packaging Notice
To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.