you need the ability to hear, you want the airplane noises to kind of come through your speaker system, and then you want that audio comment stuff to be in a different deal because you can’t hear anybody if you don’t. where do gravestones go to die? we have a variety of high quality products not found anywhere else. in the beginning, god loved the world in this way! the big rig came to a controlled stop on the shoulder of the road. in that case let's start planning your next trip! 