In order to connect the HyperJuice battery pack to the MacBook, we need to modify the MacBook/MagSafe Power Adapter to create a charging cable with the MagSafe connector.
There are 2 ways to do this.
There is the $49.95 DIY version and it only takes 5 minutes for you to modify your own MacBook/MagSafe Power Adapter to create the cable.
The $149.95 option ($99.95 when purchased together with the battery) is for customers who do not wish to do their own modification so it comes with a brand new original Apple MacBook/MagSafe Adapter (which we have to purchase at retail for $79.95) that is already modified with our Magic Box kit. So bulk of the $149.95 (or $99.95) cost comes from the $79.95 cost used to buy the original Apple MacBook/MagSafe Adapter plus the $9.95 MagSafe to MagSafe 2 Converter plus our $49.95 Magic Box kit plus a small fee for labor to do the modification.
MagSafe is an exclusive Apple proprietary technology which they do not license to anyone so nobody other than Apple is allowed to make MagSafe connectors. Magic Box is a 5 minute modification kit that modifies the MagSafe Power Adapter to graft the MagSafe connector to a standard round DC connector to work with HyperJuice.