... good flexibility, foam products even , uniform structure, smooth surface withoutadhesive, noise effective,SNR:33DB, This earplug can be washed with water ... quality earplug1.Low rebound effectIf it is too flexible, anti-noise earplug swelling suppression the canal skin, can cause ear ... be too small to close contact with the externalear canal, noise effect will be reduced. So we must observe ear ...