Fenix ARB-L18-3500U USB Charging 18650 Battery fjr it is magnesium bonded to

it is magnesium bonded to one or more amino acids

Great at evacuating sweat to keep your feet dry and comfy

Although thin

The hip belt is padded for comfort

super effective

Fenix ARB-L18-3500U USB Charging 18650 Battery fjr it is magnesium bonded toARB L18 3500U is a high capacity 18650 Li ion USB rechargeable battery with a built in micro USB charging port. It also includes a protection circuit in the anode to help prevent short circuits, over charge discharge and over heating. These USB rechargeable batteries can quickly be charged without the need for a separate charger. This not only saves you money from purchasing a charger, but also provides the convenience of not having to carry around