This icon is a small circle with another circle behind it. The first circle has the number "1" in the center of it. You cannot see the circle behind the first circle. It looks like it could be a 3D cylinder.
This is a Average 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.