The package is composed of 3000 png icons. 1500 with a shadow and 1500 without:

PNG format is compatible with all the internet browsers.  It is the best quality of picture your can offer to your users. 

ALL the icons got a perfect transparent background!

The files are all organized by categories (Basic, Business and Data, Flags, Network and security, Objects and Software developments

With Shadow and wihtout shadow icons are in a diffrent folder inside each categories.

At 9.99$ this is really a deal you want to catch!