that's what I figured it was for, but HOW do you connect it to a servo??? it's on the underside of the plane and there aren't any holes/spots for a rod to poke through to the guts of the plane.... should I put 2 90deg. bends in it to get it down the underside of the plane and up through the stomach to get inside and then connect it to the rudder servo?

I've got control arms LONG enough for this, I just couldn't find a HOLE on the underside where this had been done before; ergo, the baffled "*** is this thing?"....