This is the KangerTech Evod VV (Variable Voltage) Battery.
It is available in Black and Stainless Steel
It has a 5-click locking mechanism on the button,White LED indicator light,510/eGo threading,
3.2v-4.8v variable voltage range.
It has many safety and other features such as:
Short circuit protection.
10 second atomizer protection time-out function.
Low voltage automatic shut down protection.
Approx. 3 7/8in length & 1/2in diameter.
Battery lasts 3-6 days on a single charge.
Universal 510/eGo threading makes it easy to use most attachments.
5-click locking feature helps prevent accidental battery drain/damage.