Time to get your CURVE on! The CURVE by 4SCORE is specially designed to curve perfectly in the palm of your hand as it blends comfort, discretion, and durability all in one premium battery! The CURVE has a unique shape, which works to protect your cartridge from accidental cracks, while simultaneously exemplifying complete ease of use. This 510 thread battery is equipped with a Magnetic Connection (with 2 Magnetic Rings included) to ensure a secure cartridge fit, while making it easier than ever to switch between your cartridges. Built to suit any taste- the CURVE is capable of an Air Switch (Auto-draw) function, which allows the use of the battery without pressing the button, while the traditional Button Press feature continues to work just the same. Carrying on with suiting the needs of all custom preferences, the CURVE offers 3 variable-voltage heat settings that can be adjusted at 5 clicks of the button. A Micro USB Charger is included to make it simple to recharge again and again. The battery life of a fully charged CURVE will last beyond the first couple of days, even for the heaviest hitter.