Probably one of those whisper thin Ronald Colman type ‘taches. Easy to miss at a distance.
By the by, no ‘fire teams’ per se in God’s own army not back then anyway. Groups. Gun group, rifle group, scouts. Two JNCOs. Corporal section commander who usually moves with the rifles and scouts in the assault and a lance jack in charge of the gun group. The rifles and scouts might move independently, with the section commander moving with the scouts or they might move as one group or they might pepper pot by odds and evens in the final stages of an assault. The gun group in a section attack is almost invariably a seperate entity under the command of the section 2IC as it lays down the base of fire. That’s the theory anyway.