Answer:
I am the only word that looks the same when spelled upside down.
I am perfect with a head perfect without a head; Perfect with a tail perfect without a tail; Perfect with either neither or both.
I can speak with my hard metal tongue. But I cannot breathe, for I have no lung. What am I?
Never resting, never still. Moving silently from hill to hill. It does not walk, run or trot. All is cool where it is not. What is it?
My voice is tender my waist is slender and I'm often invited to play. Yet wherever I go I must take my bow or else I have nothing to say.
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.