There is an image of the back of a mailing envelope. Over the bottom right hand corner of the image there is a circled check mark that seems to be indicating that an action has been completed involving the envelope.
This Received icon is a responsive icon. This means that it's optimized for four resolutions, from tiny 16x16 until highly detailed 80x80. The style comes from the latest Microsoft Office
, which makes it perfect for any Windows applications, in particular, those with ribbon toolbar control. Unlike other icon packs that have merely hundreds of icons, this monster icon pack contains 16,000 icons, all in the same style and quality.