These eartips are very elastic and fit comfortably into the contours of your ears, keeping your earphones comfortably in place and reducing ear fatigue. Since these eartips are made of memory foam, they adjust themselves to the contours of your ears by getting softer based on the interaction with body heat. The thick ear muff design reduces ambient noise and enhances the bass experience. Significantly elevating the sound insulation effect of headphones, these memory foam eartips bring down sound signal transmission loss to below 2dB.