The Voluna V2 has upgraded in many ways like ease of building, smoother aiflow control, an easier way to fill your favorite juice, etc. The building experience is vastly improved due to it’s unique and innovative 2 post lego-like posts making it simple to center your builds, not to mention the amount of space the deck has for those crazy builders out there. With this factored in the Voluna V2 can produce clouds that you’d never expect from an RTA. To fill the juice is easy as pie, there is an little indicator that tells you where to push the top cap to reveal a fill hole. The fill hole is made of rubber making it expandable to fill with almost anything from droppers to unicorn bottles with ease.