Idea of Open Envelope Icon
When you have email messages available to read you will see a envelope with the top flap open and inside a piece of paper. This shows that you have messages available in your email inbox.
This is the Open Envelope icon for Windows 10
. Here we go. Optimized for 32x32 px, these are the simplest icons in the line style. Downloadable formats are PNG and SVG, among others. Icons8 icon pack is unique in providing a huge number of icons designed by the same team of four designers who create the new icons every working day in the same style and with the same quality. Same cool as the Bat Face, huh.