It's an image of a long diagonal line from the top left to the bottom right. It's cutting a signal image in half diagonally. The signal image is a small circle in the middle with two partial curved lines emanating from each side.
This Offline icon is made in flat color style
. This format was developed by Icons8 designer team and became immensely popular for use in web and mobile applications. Feel free to download this icon in PNG format for free, or unlock other formats for $5. Unlike other icon packs that have merely hundreds of icons, this monster icon pack contains 5,900 icons, all in the same style and quality.