The first few months with a new MacBook Air or Pro are always the best. Everything works perfectly, the aluminum design is totally unblemished and best of all the battery seems to last forever. But within a few months that battery will likely start to lose its luster, and after a year or two you won’t be able to go very far without a charging cable on hand. Thankfully there is a solution, and it doesn’t even require buying a new laptop.

BatteryBox is the smartest MacBook power accessory we’ve ever seen. It uses clever software and a unique design to offer a solution for your battery needs that should keep you going all day.

First let’s talk about that design. Apple’s come down pretty hard on companies that try to copy its MagSafe technology, but BatteryBox claims to offer an alternative that still works without breaking any rules. Instead of attaching magnetically it uses a clip-on setup called SnapFit that stays attached, though it won’t disconnect quite as seamlessly.

The cord itself looks pretty nice, though those clips are a little less attractive. The power brick itself isn’t particularly sleek either, though it is compact. Inside it packs a 16,000mAh and promises 3000 cycles of use, which should outlast your actual MacBook.

One of BatteryBox’s best features is the way it actually powers your MacBook. Instead of simply re-charging the laptop it bypasses the battery entirely and pushes energy straight to the device. That means it won’t wear down the MacBook’s battery over time. Of course, it also means you can’t use your laptop without the BatteryBox plugged in once your battery is drained, but it’s small enough that this should be a real issue.

The entire thing also runs on the company’s own BatteryOS software, which is designed to deliver as much power as possible. It boasts 10 to 40 percent more capacity than a regular battery of the same size, and powers iOS devices 15 times faster than the competition thanks to a built-in USB port. It also features Lossless Power Delivery, meaning your BatteryBox won’t slowly run out of juice when it’s not in use.

As a result you can power a 13-inch MacBook Pro for 7.4 hours or a 15-inch Pro for 5 hours. The 11-inch MacBook Air gets 12 hours of power from BatteryBox, while the 13-inch Air somehow gets ever more at 13 hours of life. As for mobile devices, the accessory can charge an iPad Air for 22 hours, an iPad mini for 25 hours, or an iPhone 6 for 75 hours.

BatteryOS is also constantly recording data for crowd-powered field research so it will get smarter after time. The company notes that each BatteryBox does have a specific ID number, but there’s no way to know which customer is connected to each number.

BatteryBox doesn’t come cheap. It costs $219.95 for the battery and all four SnapFit connectors along with a 1 year warranty. Still, that’s a lot less expensive than buying a new MacBook entirely.