The Surefire SF18650B is a high-performance rechargeable lithium-ion battery designed to provide reliable power for SureFire flashlights and other high-drain devices. With a capacity of 3400mAh and a voltage of 3.7V, this battery offers long-lasting energy and consistent performance. The SF18650B features built-in protection against overcharge, over-discharge, and short-circuit, ensuring safe and efficient operation. Ideal for both professional and personal use, this rechargeable battery is a dependable choice for powering your essential devices. SureFire 18650 Micro USB Lithium Ion Rechargeable Battery SF18650B