Answer:
What is that over the head and under the hat?
A little pool with two layers of wall around it. One white and soft and the other dark and hard. Amidst a light brown grassy lawn with an outline of a green grass.
I'm full of holes, yet I'm full of water.
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.
It can cause deflation of tires when dropped from the rear of spy cars.
If itβs information you seek, come and see me. If itβs pairs of letters you need, I have consecutively three. What am I?