From Halopedia, the Halo wiki

Composition L, commonly shortened to ComL,[1] is a type of high explosive mixture used by the United Nations Space Command in the M9 High-Explosive Dual-Purpose Grenade. It is a generally stable mixture which is extremely destructive when primed and detonated.[2] Only 0.19 kg of ComL is used in one grenade. ComL is relatively inexpensive to use and is effective at propelling the shrapnel from the grenade.[3]

List of appearances[edit]