These ego style, but not ego threaded, pen style batteries are made by Volcano Fine Electronic Cigarettes. These types of batteries and systems are typically recommended for users who do not want larger volumes of vapor and prefer to use liquids with higher nicotine levels (typically 8 mg or more). These batteries produce 3.7 Volts of current, and come in two different sizes ranging from either 650 mAH to 900 mAH. These batteries act as a USB Pass-through allowing you to charge and vape at the same time.
Convenient for vaping wherever you may be!
Dave's Tips: the 650 mAh will typically last between 4 to 6 hours per charge and the 900 will typically last 6 to 8 hours per charge. Both estimates assume continuous use.
Pro Tip: These cells have a minimum Ohm limit of 1.21 Ohms, and will not produce vapor with atomizers rated at 1.2 Ohms or below.