There are 5 lines running horizontally equally spaced. As the lines moved down in the set each one is shorter than the one before showing a gradual decrease in over all size. Pretty much like a signal strength image but on its side
This Sorting 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 6,000 icons, all in the same style and quality.