The E-5s is one of the default weapons for the Specialist. This means it shares the same statistics as the other default Specialist weapons for the other factions. This also means that modifications can not be equipped, which limits the overall potential of the weapon.
Being a sniper rifle, the E-5s is most effective at mid to long range, as it does not fare as well in close range. The E-5s is able to output faster follow-up shots and has less recoil compared to the IQA-11 and NT-242, but is not as high in damage per shot.
The E-5s originally appeared in Star Wars: Battlefront series made by Pandemic Studios. This rifle was also seen in the Star Wars: The Clone Wars series.