Idea of 4k Icon
This is a square, with the top and bottom lined with several smaller squares. The characters "4K" are in the middle of the big square. There are eight squares that align both the top and bottom of the big square.
This 4k icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 6,100 icons, all in the same style and quality.