Grievous Gladiator's Copperskin Helm is part of the transmog set Grievous Gladiator's Ironskin Armor (Monk only), which the Appearances collection lists in 2 versions. The other 13 pieces:
Built from the World of Warcraft client build files and recorded Auction House snapshots.
Where Grievous Gladiator's Copperskin Helm Fits
Other Items Named Grievous Gladiator's Copperskin Helm
4 other items in the current build are also called Grievous Gladiator's Copperskin Helm. 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 Copperskin Helm
Blizzard numbers items as they are created, so the named items next to ID 100356 (100351 to 100361) were usually added in the same batch as Grievous Gladiator's Copperskin Helm: the same quest line, zone, vendor or reward set.