Our car sponges contain nano-silica. It can clean the glass of the car. Its use method is very simple: 1. Clean the dust or debris on the surface of the glass. 2. Open the lid, rub the sponge on the surface of the glass, and gently wipe it. 3. Wait 5-10 minutes and rinse with water. And can withstand the worst shocks, significantly reducing the risk of fragmentation or fracture.