Our foam earplugs contain a PU memory sponge. It can have good comfort and support, very close to the ear canal; Fit the curve of the ear canal, no pressure for a long time to wear, comfortable. The way to use it is simple: 1. Clean and dry your hands. 2. Take out the earplug and roll it into a small cylinder with your thumb and forefinger. 3. Gently place the compressed earplug into the ear canal. 4. Gently turn or press the earplugs to make sure they are fully in place. Excellent sound insulation to help you enjoy a quiet time. Effectively isolate noise and improve sleep quality.