Binding

[Colaboy]

Hi.
I';m very new to all this so, apologies if this is a really stupid question.
I';ve no idea how the binding process works and I';m wondering if it is possible to bind more than one X4 to the same controller.
I';ve just built a second X4 out of bits and would like to try and fly them in sync (ish).
I';d just give it a try but I only have one battery at the moment.

Thanks