Answer: RGTS

AnswerCrossword Clue
RGTSGrps. of battalions
RGTSArmy units: Abbr.
RGTSArmy groups.
RGTSMil. divs.
RGTSMil. groups
RGTSMil. units
RGTSCols.'s commands
RGTSGroups headed by cols.
RGTSThey make up divs.
RGTSLarge mil. units
RGTSArmy units (abbr.)