uhmmm....i believe that was a gun owned by one of the members of ZZ Top.
or...it could be the throw-in air freshener Tribble, that you get with every mall ninja special-ops weapon du jour, such as this one.
i was thinking of getting one, but all the rails are used up, so that would leave no room for the training wheels, or a handle for my caddie to carry it around for me.
To the original poster....get a rear sight for your DS, if it did come as shown. You can pick up a rear sight, folding or fixed for as low as $75 if you shop. stay away from the air-soft stuff, unless you like paying more than once. other than that, as someone already mentioned, pick up some magazines, and extra ammo, and get out and learn how to use it....before turning it into anything that looks like that mall ninja piece.