Good Riddles

Question: Those who make this item, don't use it. Those who BUY this item, have no need for it. But those who USE this item, never see it. What is the item?

Question: How can you flip the shape upside down by moving only two of the sticks?

Question: what comes in hard comes out soft and you blow ???????????????????????????????????????/

Question: What is at the end of a rainbow?

Question: I have no wings but I fly,
I have no teeth but I bite.

What am I?