The icon shows a round button with the number one. it is three circles that appears to make a base for the button that has the number one prominently shown on the front.
This Expensive 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.