Ultritium compound 902, a deritative of ultritium, was a weapons grade chemical explosive used in small munition devices and Type 43 fusion detonators. Until exposed to and activated by an energetic gamma pulse, this explosive was stored in an inert liquid form. The explosive was activated by a Type 12 Hillebrand detonator. In 2367, this explosive was stored on aboard the Federation starship USS Enterprise-D.
In that year, ultritium compound 902 was on a list of explosives that Lieutenant Commander Data and Counselor Deanna Troi searched through in an attempt to find one that could produce enough energy to release the USS Enterprise-D and an alien ship from the Tyken's Rift. (TNG: "Night Terrors")