GB, isopropyl methyl phosphonofluroidate, Zarin
GB is a volatile, rapid acting, lethal nerve agent. It is an odorless and colorless volatile liquid at room temperature. It is an inhibitor of the enzyme acetylcholinesterase (AChE), which is required for the function of many nerves and muscles in every multicellular animal.
Old Chemical Weapons Reference Guide (1998)
Chemical Agent Identification Sets (CAIS) Information Package (1995)