The DKEii Variable Voltage Battery brings back one of the most popular cartridge battery devices designs ever. The rotary pop-up 510 thread, encased in a car fob-like shape, is an unparalleled ergonomic design that feels like it belongs in your hand. Powered by an internal 650mAh li-ion rechargeable battery core, the DKEii VV Battery is equipped with four variable voltage settings, preheat mode, LED indicator lights, memory function, and multiple safety protections.