SD-7, also known as "Essdee", was a scout droid of the Galactic Republic during the High Republic Era, and possessed masculine programming. As part of the onboard tool kit, he was kept on a maintenance shuttle that was docked to the cruiser called Steady Wing. The Steady Wing was destroyed by the Nihil pirates through sabotage, leaving only a few survivors who fled on the compromised maintenance shuttle, ultimately crash landing on the moon of Wevo. Avon Starros, an aspiring inventor, discovered SD-7 within the tool kit and decided to bring him along when the group departed their initial crash site in search of improved shelter. Starros utilized SD-7, who had only a limited power supply, to find a suitable cave for the group to take refuge in. While still on Wevo, SD-7's power was completely depleted; however, Starros ensured he was taken with her when they were eventually rescued.