Buy three and save! SV Rechargeable Lithium-Ion XL Batteries last 30% LONGER for more than 350 puffs before needing recharge. Be ready to be energized because we have Batteries with a little bit of color to brighten up the day. SV Rechargeable Lithium-Ion High-Capacity Batteries last well more than 350 puffs before needing recharge. These little powerhouses have are full of Sophistication & Vitality. You would be amazed at how much technology is packed inside. There is a PCB board (Printed Circuit Board) that regulates the voltage flow to the cartridge, controls the air-flow monitor for when you inhale and it talks to the vaporizer. It's the boss. "Hey, Vaporizer! Get to work! We have some delicious satisfaction to deliver!" And it all works seamlessly and instantly. Yes, we have a magic machine that delivers awesomeness. When the battery needs a recharge, the light will blink - basically it signals you to feed it. Unscrew from the cartridge, screw it on the charger and then plug it in. That Simple. When fully charged (about 2-3 hours) the light on the battery will go out. The chargers have a brain too and won't overcharge the batteries, so nothing to worry about there either! But since no one wants to run out of battery power, it makes sense to own a bunch of them. So get some extras. You can choose from many different colors that are Stylishly Vibrant! And if you want, you can have one in each color! Get them all!