RC Tanks newbie question

[West Man]

Hi

I saw a set of neat RC Tiger tanks. The tanks were tiny and fit in
the palm of your hand. I would like to buy 4 with each one having its
own freq. However, only 2 channels are offered. 27 and 49 mhz I
think. Whatever the two common ones are.

Is there anyway to alter this?

Thanks from a newbie