Strefa czasowa -7 and other 65,000 icons from Icons8 icon pack follow the visual guidelines of the operating systems: Windows, iOS, Android KitKat, and Material. PNG format is free up to 100x100 px. Icons are availble for download in PNG and vector (SVG, PDF, EPS, and more).
A timezone -7 icon is a foldout map symbol and both sides of the map the lines will be straight. However, on the top and the bottom will be a zig zag pattern to show the foldout. An important aspect of the timezone -7 icon is that there will be a -7 in a circle on the map.