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Fogstar Energy Green 21700 Battery (4000mAh)
The Fogstar Energy FS4000 21700 battery is built for vapers who need high-performance power for demanding setups. With a 4000mAh capacity and a robust 25A continuous discharge rate , this rechargeable cell is ideal for sub-ohm vaping and high-drain devices .
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Orders placed before 3pm (Monday to Friday) are dispatched the same day wherever possible; orders placed after the 3pm cut-off are dispatched the next working day. Free tracked shipping on all orders over £350 (ex VAT).
Fogstar Energy FS4000 21700 Battery
The Fogstar Energy FS4000 21700 battery is built for vapers who need high-performance power for demanding setups. With a 4000mAh capacity and a robust 25A continuous discharge rate, this rechargeable cell is ideal for sub-ohm vaping and high-drain devices.
Engineered with durability and safety in mind, the FS4000 is a flat-top, non-protected battery, recommended for use in regulated devices with built-in safety features. As part of Fogstar’s Energy Series, each cell undergoes strict quality testing to ensure reliable performance and long-lasting power.
Key Features
- Battery Type: 21700 Lithium-Ion
- Capacity: 4000mAh
- Continuous Discharge Rate: 25A
- Voltage: 3.6V
- Rechargeable, Flat-Top Design
- Non-Protected Cell
- Perfect for Sub-Ohm and High-Drain Applications
- Designed for regulated vape devices
Safety Information
- Only use according to manufacturer’s instructions.
- Charge with a dedicated Lithium-Ion charger.
- Never leave batteries unattended while charging.
- Keep away from children and animals.
- Inspect wraps and insulators regularly for damage – repair or recycle if compromised.
- Expected cycle life: 200–500 charges before noticeable capacity drop-off.
- Do not crush, incinerate, or modify the cell.
What's in the Box
1 x Fogstar Energy FS4000 21700 Battery
Important Notes
Always confirm compatibility with your device before use. For maximum safety, replace worn batteries promptly and recycle responsibly at end of life.
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