Phase I ARC Trooper Armor

Phase I ARC Trooper Armor was a full plastoid armor suit worn over a form-fitting bodysuit. It was equipped with heavier armor on the forearms, thighs, and chest, and had an advanced helmet that contained a hardened long-range comlink. A kama was worn around the waist, which offered extra protection to the legs and groin. Each armor set featured a built-in load-bearing harness and survival pack. An experimental armor, it was a field-test and something of a prototype for the Phase II clone trooper armor, which would indeed end up being based upon the Phase I ARC trooper gear.

Throughout the Grand Army of the Republic's deployment, ARC troopers would often be the first among the clone ranks to get new gear, with their field testing allowing armor designers to finetune armor for wide-scale usage. Indeed, ARC troopers were supplied with Phase I ARC Trooper Armor early in the Clone Wars, using the gear as a field-test for the looming phase II clone trooper armor the ARC gear was a sort of a prototype for. Clone ARC Commanders of the Rancor Battalion wore Phase I ARC Trooper Armor while overseeing clone training on the clone homeworld of Kamino. Later, the ARC officers wore that gear in the defense of Kamino. After their promotion to ARC troopers in the aftermath of that battle, clone troopers Fives and Echo were equipped with Phase I ARC gear. Both wore their armor during the Battle of Lola Sayu, where Echo was presumed dead. The ARC ranks, including Fives, would transition to Phase II ARC Trooper Armor sometime later, while the overall clone ranks were given the finalized Phase II gear the ARC troopers had helped pave the way for.

Phase I ARC Trooper Armor first appeared in the Star Wars: The Clone Wars episode "Clone Cadets," which premiered on Cartoon Network on September 17, 2010, alongside the episode "ARC Troopers" as an hour long premiere for The Clone Wars: Season Three. The armor was first identified in the sourcebook Knights of Fate. However, it was not outright confirmed as the gear seen in The Clone Wars Season Three until the release of Rise of the Separatists.

In The Clone Wars, the ARC trooper gear later identified as Phase I ARC Trooper Armor was intended to foreshadow the shift from Phase I clone trooper armor to Phase II armor among the standard clone ranks. Dave Filoni recognized that, by the end of Season Three, Phase I armor would have been the main gear the audience had seen and the time had come for a change. As such, the crew created the ARC trooper armor as a sort of in-between prototype that came after Phase I armor but before Phase II. Discussing the "many reasons" the crew decided to create the in-between armor phase, Filoni pointed towards the fan 501st Legion as an inspiration because its members, having only just figured out how to make The Clone Wars inspired Phase I armor, dreaded the day the show would shift towards Phase II. Seeing that his crew was already preparing for the debut of Phase II armor that would make its first physical appearance in The Clone Wars: Season Four, Filoni decided to create a bridge between the show's Phase I and Phase II designs.

Story wise, he also realized it made sense because of how early certain events fell in the war's timeline: ARC troopers in such gear first appeared in the Season Three episode "Clone Cadets," a flashback episode set during the show's first season. In designing the gear, Filoni tasked the crew's design and concept artists, such as Wayne Lo, with combining elements of the different armors. Most notably, the helmet is a hybrid between the standard Phase I and Phase II clone armors.

• Star Wars: The Clone Wars The Complete Season Three — Featurette: "Creating Kamino"
• Knights of Fate
• Rise of the Separatists