SF18650B Surefire Battery

The new champion among SF18650 rechargeable batteries 3.6 volts / 3500 mAh deliver extended runtime MICRO-USB charging facilitates charging via a variety of power sources
The SF18650B is a Lithium Ion-protected 18650 battery with MICRO-USB charge capability. This allows the user to conveniently charge the battery using any USB power source such as a USB wall charger, computer/laptop, power bank, or automotive USB port using the included MICRO-USB to USB cable. Additionally, an external 18650 compatible CC-CV cradle charger (not included) can be used to charge the battery; possibly at a faster rate if so equipped.