130wH Valence n-charge external battery and 120w AC/DC Kensington adapter bundle for the Macbooks
This bundle will come with the external battery listed here and Kensington 120w AC/DC adapter.

You can use the Kensington AC/AC adapter both power and charge your Macbook Pro, Macbook, Macbook Air from any power source! And when your nowhere near power you can use the external battery to keep you running for additional hours! Oh, by the way, the external battery WILL charge your internal Macbook battery. No worries getting caught with a dead internal battery if you need to be truly detached!
Manufacture's product description for this external battery: