C-7 foaming explosive

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C-7 Foaming Spray is a highly explosive compound that is used in demolitions by UNSC forces. It is comprised of various chemicals that react to a signal electrical current shock sent through a detonation switch. It is liquid in vacuum, but once contact with a hard surface and oxygen occurs, it becomes a foaming, semi-solid adhesive resin.[1]

Uses

Its most notable use is when Corporal Locklear uses it to destroy the Forerunner Crystal (the reason why the Covenant were chasing them), leading to his death.[2]

Trivia

  • In the present, there is a very effective explosive called C-4, possibly a precursor of C-7.
  • C-4 is short for "Composition 4", therefore it is likely that C-7 means "Composition 7." It is also likely that it is simply a codename based the order in which it was developed, not an indicator of its explosive power (i.e. being 1.75 times as powerful as C-4).
  • It is mentioned only once when Master Chief talked about his training as a Spartan-II.
  • The most likely reason C-7 was developed was so that the users would be able to simply spray it onto the surface.
  • C-7 may be another reference to 7.
  • In Halo: Fall of Reach, Samuel-034 used C-7 to destroy an airlock while trying to capture a rebel leader.
  • The properties of C-7 are more than likely similar to the yellow expanding foam used for insulation and sealing in construction.

Sources

Template:UNSC Infantry Weapons