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 a responsive icon. This means that it's optimized for four resolutions, from tiny 16x16 until highly detailed 80x80. The style comes from the latest Microsoft Office
, which makes it perfect for any Windows applications, in particular, those with ribbon toolbar control. Unlike other icon packs that have merely hundreds of icons, this monster icon pack contains 16,000 icons, all in the same style and quality.