The death box is a small box that makes a loud screeching noise whenever it is turned on.
Splinter Cell: Chaos Theory AD CampaignEdit
In the fifth splinter cell video, Radness Overload. The death box is plugged in by Rocco outside of a store and buzzes loudly until a bypasser turns it off.
According to the Mega64 Time commentary for Radness Overload, the death box was purchased at a thrift store for two dollars and no one has any idea what it is actually supposed to do.