The new eGo long lasting battery is the newest generation replacement battery for the eGo. This eGo is also compatable with the 510 atomizer and charger if it was purchased at Besteciggy.com or a Besteciggy retail store location. Customers have reported upwards of 12 hours of battery life on one battery depending on use. Simply click on the button on the batter 5 times quickly to turn this battery on. Leave it that way, OR click it 5 more times quickly to shut the battery off. This is a great feature for people who like to put their batteries in their pockets as it eliminated the possibility of wearing down the battery by accidentally turning it on.