Read from the World of Warcraft client build files.
How Riverbed Chestguard Compares
Who It Suits
Plate is the armor type Death Knight, Paladin and Warrior wear. With Strength or Intellect, Riverbed Chestguard suits Arms, Fury and Protection Warrior; Holy, Protection and Retribution Paladin; Blood, Frost and Unholy Death Knight.
Transmog Sets
Riverbed Chestguard is part of the transmog set Swarmbreaker's Battleplate (Warrior, Paladin and Death Knight only). The other 16 pieces:
Built from the World of Warcraft client build files and recorded Auction House snapshots.
Where Riverbed Chestguard Fits
Other Items Named Riverbed Chestguard
2 other items in the current build are also called Riverbed Chestguard. Same-name entries are usually a different rank, faction, quest stage or reward track of the same object.
Blizzard numbers items as they are created, so the named items next to ID 81083 (81078 to 81088) were usually added in the same batch as Riverbed Chestguard: the same quest line, zone, vendor or reward set.