The Fenix ARB-L21-5000U USB-C Rechargeable 21700 Battery delivers dependable 5,000 mAh power for modern high-drain flashlights and gear. Built around a 3.6 V Li-ion cell with an integrated USB-C charging port, it lets you plug directly into common USB-C cables without needing a separate charger, making it a practical upgrade for compatible 21700-powered lights.

This model is ideal for users who want extended runtime with straightforward charging for range sessions, training days, or everyday use with their firearm-mounted or handheld lights. Multi-layer protection circuitry and pressure relief vents help guard against short circuits, overcharging, and overheating, providing confidence in demanding conditions while reflecting Fenix’s reputation for thoughtful engineering and reliable illumination products.

• Manufacturer: Fenix
• Model: ARB-L21-5000U / FX-ARBL215000U
• Capacity: 5000 mAh
• Voltage: 3.6 V
• Charging Port: Built-In USB-C
• Charging Cycles: Up To 500
• Safety Features: Protection Circuitry And Pressure Relief Vents