The logo for Sigma pretty much looks like the letter E. The symbol has a deep bent in the middle towards the right and the middle ledge doesn't protrude as much as the top and bottom ledge.
This Sigma 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 15,900 icons, all in the same style and quality.