VS2010 Class member icons

[Glen Harvy]

Hi, The VS2010 icon for a Property value is a memoedit box with a hand/finger pointing down in the top right corner. I'm sure you all know it well so excuse my description. Now if that icon has what appears to be the reverse of a DL envelope over-imposed on it in the bottom left corner, what does that property become? Mailable :-) How can I access said property and where can I find an explanation of these icons. Thanks, Glen.