This page shows the different variations of the Żaluzje w dół from an Icons8 icon pack. Feel free to resize and recolor the icon, and then download the icon in PNG format for free. Icons are available in PNG and vector.
This icon shows a square window that is half covered in blinds, and half uncovered. The blinds cover the top half and under there is an arrow pointing down alongside a pulley to lower and raise the blind.