The icon shows five horizontal lines on top of each other. The middle 3 lines are shorter than the top and bottom. To the left of the 3 shorts lines is a triangle with it's base aiming left and its point aiming right.
This is a Indent icon. We've made it in iOS style
, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 13,300 icons, all in the same style and quality.