The A08.2 was the one of the outfits used by the Sith Order

Sith Order Organization Reconstituted Sith Empire

during and after the Great Galactic War

Great Galactic War Event Great Galactic War (3681BBY - 3653BBY)

.
The Sith Order was less regulated in its choice of armor and uniforms than the Imperial Army

Imperial Army (Sith Empire) Organization Reconstituted Sith Empire

, but to some extent its members were also required to wear a certain type of outfit while on mission. This outfit was issued to the warrior

Sith Warrior Organization Galaxy-Wide Organizations

's branch of the Order.
The set was not much different from the others, providing moderate protection to the wearer's body, legs and arms.