The Eleaf iStick Power 2 is the next generation of the iStick range. Who is the Eleaf iStick Power 2 for?. How long does the Eleaf iStick Power 2 battery last?. For versatility, the iStick Power 2 features a threaded 510 connection, opening up a range of possibilities for pairing with a variety of different tanks, coils and e-liquids to suit your preferences.