M383C Linear Shaped Charge Demolition Kit
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The M383C Linear Shaped Charge Demolition Kit is a UNSC explosive. Not much is known about this, although the name suggests it is not entirely an explosive, instead holding several of these perhaps small sized charges. It is also possible that it may function as a satchel charge.
Trivia
The mechanism by which the explosion of the Type-2 spike grenade is directed is similar to that of the M383C Linear Shaped Charge Demolition Kit.
Sources