Semtex

The Semtex is a type of grenade as seen in the Call of Duty: Modern Warfare 2 Multiplayer Trailer.

Real Life Use
The Semtex was first developed by the Czech Republic in the 1950's, and was similar to C4 except it could withstand more heat without reacting. It saw widespread use, especially by Libya and North Vietnam. Now, because of government restrictions, most of the 10 ton annual production of Semtex is exclusively domestic.

In Game Appearance
The first in-game use of Semtex was seen during the Modern Warfare 2 Multiplayer Trailer, working like a regular grenade and having the same principals as the Call of Duty: World at War Sticky Grenade. However, unlike World at War's sticky grenades, Semtex shows up on the grenade danger indicator.