It is plastic. In the positive aspects, it is durable and it does not slip in the hands at all. Additionally, its grip is non-slip to the point where it gets stuck in pockets and comes out with the phone inside. One time it got stuck like that and my phone fell luckily on the carpet. And another time, when it fell from a height of 1.50 meters onto a concrete pavement with gravel, it made a dent in the bottom right corner. This shows a lack of elasticity, which can be a bit dangerous. On the positive side, it is not easily removable. I would prefer it to be elastic.