This Signin 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 4,400 icons, all in the same style and quality.
This is an image of a circle. The circle has a small blank area at the top of it. Inside the circle is a downward facing arrow that begins at the blank area of the circle and ends just past the center of the circle.