The arms deal update

We'll start with the first post about the new CS:GO update , The Arms Deal Update, which lets you experience all the illicit thrills of black market weapons trafficking without any of the hanging around in darkened warehouses getting knifed to death. The Arms Deal Update lets you collect, buy, sell and trade over 100 all-new decorated weapons that you can equip in-game.

You can start collecting decorated weapons via timed weapon drops just by playing CS:GO on official and community servers. You can also get them by opening dropped weapon cases with the appropriate key, or by trading with other players through Steam’s Trading interface. Additionally, any decorated weapons you’ve found, bought or traded can be sold on the Steam Marketplace. Last but not least, as part of the Arms Deal Update, we’ve added two new stock weapons available to everyone, 
the M4A1-S and USP-S.