This Przesuń w dół 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 15,000 icons, all in the same style and quality.
The "swipe down" symbol here consists of a circle, with a straight line extending down from its lower half in the middle, with two diagonal, upward-reaching lines extending upwards from the end of the line. It is a circle with a downward-pointing arrow extending from it.