8942-LQ99
From Halopedia, the Halo wiki
8942-LQ99 is the serial number for an experimental drug used by the UNSC. This drug is a carbide ceramic ossification catalyst to make skeletons virtually unbreakable. It was one of several drugs that was used on the Spartan-III supersoldiers, and was significantly more safe that the drugs used on the Spartan-II supersoldiers.