While functional, the buckler's a vestige of trad'l Aztalan war gear that serves as a badge of rank for veterans. Over time, it would shrink in size to a purely decorative shoulder epaulette.
Armored infantry w/LMG. The half-exo leg units' primary purpose is to support the weight of the armor & various kit such as a climate control/filtration system worn in conjunction with a full helm.
Post-Christmas posting, armored life vest of an early, obsolescent design still commonly worn by river gunboat crews. Flotation bags are multi-celled for some degree of redundancy in the event of puncture damage.