Also available as 2-pack for 399:-

Smoketower Twist Battery with adjustable power and long battery time for your 510 cartridges. 

The pen's power voltage ranges from 3.3V to 4.8V, which can give you smooth tasteful hits and hard-hitting clouds.

Instructions: Click 5 times on the pen to start the pen. Click and hold once to start inhaling and release when completed.

Thread: 510
Battery Capacity: 1100mAh
Voltage: 3.3V > 4.8V