R3-A2 has a transparent dark green dome used by other astromechs like R2-D2. The dome has orange lines across it and a white eye. He has white astromech legs and a white astromech body with orange markings on the control panels.
R3-A2 was an orange R3-series astromech droid. It was seen in Echo Base during the Battle of Hoth in 3 ABY.
Like other R3 droids manufactured by Industrial Automaton, R3-A2 was designed for high tech work on military installations. The clear plastex dome showed off a newly-updated Intellex V computer system, which contained detailed statistics on thousands of military starships. R3-A2 could hold up to 5 hyperspace jumps in active memory, and could also coordinate piloting coordinates and approach angles during combat. His eye was a round kind unlike most R3 units.