Nomad is a company that sells ultra-rugged charging cables, made out of ballistic nylon, extra thick wire, and kevlar to make sure that your charging cable doesn’t fall apart. Its latest cable takes it a step further by adding a small integrated battery pack into the Lighting cable itself to charge up your phone even without an outlet.

It costs $39.95, which isn’t cheap for a 2350 mAh battery pack

It works similarly to Apple’s own iPhone 7 battery case, where the cable charges the phone first, and then charges the built-in battery once your device is fully charged. But it’s actually kind of reasonable once you compare it to Nomad’s standard Ultra Rugged Lightning cable, which retails for $29.95. When you’re shelling out for a high-end cable anyway, the extra $10 for the ability to charge up your iPhone on the go seems like it’d be worth the price.

For as long as Nikola Tesla’s dream of wireless electricity remains outside the grasp of physics, we’re stuck with cables, wires, and plugs to keep our gear charged up. We might as well make the most of them, even if that means adding in a battery pack.