Remote Controlled Heli

I got a heli fight against mosquitoes away from Radio Shack for Christmas. It'sa lot of fun, but on the bottom of the helicopter there is a button that goes from left to right. my owner's manual threw me: (
and I do not know what he does. So what does it do? I think it might be DIF. frequencies.

Yes, this button determines the frequency of your Heli is sure you know who is Heli yours when you and a friend fly helis multible.

does not mean you dragonfly?