NEW TRIP TWICE BATTERY with bottom charge so you can charge and use at the same time, which counts every hit up to 10 seconds, gives you a view of percentage left in you battery with easy to view LED screen to make sure you are always aware of you usage and has variable voltage control 3.3 to 5 " we recommend 4.2 volts for highest quality use". Just 45 minutes to charge. 510 THREAD GREAT FOR YOU TRIP TWICE MAGNETO ATOMIZERS AND CARTRIDGES FROM YOUR FAVORITE VAPE COMPANIES