Gold- Mature, switches into Duty Mode quickly.
Blue- GIR-like and immature, takes several tries to go to Duty Mode but goes back to Blue Mode quickly.
Purple- violent, not willing to give up easily, goes into Duty Mode as soon as a command is given.
Red- standard SIR Unit Duty Mode.
SIRA is a silver GIR-looking SIR Unit that is as tall as GIR, and is almost to Mas's chest in height. Her eye color varies. In disguise, she is dressed like a fox. The disguise is similar to GIR's doggy outfit, but with a discreet zipper in the front of the costume.
Mas- Sisterly. SIRA and Mas will do anything to protect each other.
GIR- GIR and SIRA are best friends, and know that their masters fancy each other's master.
Zim- SIRA knows Mas likes Zim and Zim likes Mas, but is sworn to secrecy by GIR and Mas, therefore, she acts awkward around Zim when she's in Gold Mode.
Dib- SIRA likes to bite Dib. She thinks his human-boy-flesh is yummy.
Gaz- SIRA is scared of Gaz, even when in Purple Mode.