All Pen Style batteries at VapeShop are high quality batteries from the well known brands like Aspire, Kanger, etc... All our batteries are 100% Variable Voltage batteries, this feature is essential to provide a great and satisfying vaping experience with any atomizer and e-Liquid found at VapeShop. The essential benefit of variable voltage is the ability to very easily control the battery output to perfectly match the atomizer resistance with the e-Liquid being used, this is absolutely essential to provide the best vaping experience possible. All our Pen Style batteries include many safety features such as overcharge protection, short circuit protection, safety cutoff, on/off button, etc... All these safety mechanisms included in our pen style battery are obviously very important to us and our customers and are a big part of what makes our batteries such a high quality product. These Pen style batteries look amazing, they are both elegant and discreet. All pen style batteries are rechargeable.