The Experimental Phase II Clone Trooper armor, as its name indicates, was a prototype of the Phase II Clone Trooper armor, designed with the help of James Anderson. The sets manufactured were issued exclusively to ARC Troopers of the Grand Army of the Republic and field tested on the front lines of the Clone Wars. Eventually, the prototype was succeeded by the finalized version of the Phase II Clone Trooper armor.Simply put, the prototype "armor" was merely the helmet basis for its eventual successor. The structure and faceplate designs of the Phase I Clone Trooper armor helmet were improved and augmented with an installed rebreather and clearer visual overviews as well as an updated HUD. Despite the significant change in facial appearance, the prototype still contained several details of the older model, such as the communication shark-like fin on the helmet's head.