Grievous Gladiator's Plate Chestpiece is part of the transmog set Grievous Gladiator's Plate Armor (Warrior only), which the Appearances collection lists in 2 versions. The other 6 pieces:
Built from the World of Warcraft client build files and recorded Auction House snapshots.
Where Grievous Gladiator's Plate Chestpiece Fits
Other Items Named Grievous Gladiator's Plate Chestpiece
4 other items in the current build are also called Grievous Gladiator's Plate Chestpiece. Same-name entries are usually a different rank, faction, quest stage or reward track of the same object.
Items Numbered Next to Grievous Gladiator's Plate Chestpiece
Blizzard numbers items as they are created, so the named items next to ID 100521 (100516 to 100526) were usually added in the same batch as Grievous Gladiator's Plate Chestpiece: the same quest line, zone, vendor or reward set.