Read from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
How Slashproof Business Plate Compares
Who It Suits
Plate is the armor type Death Knight, Paladin and Warrior wear. With Strength or Intellect, Slashproof Business Plate suits Arms, Fury and Protection Warrior; Holy, Protection and Retribution Paladin; Blood, Frost and Unholy Death Knight.
Transmog Sets
Slashproof Business Plate is part of the transmog set Dorn Defender Armaments (Warrior, Paladin and Death Knight only). The other 16 pieces:
Blizzard numbers items as they are created, so the named items next to ID 221069 (221064 to 221074) were usually added in the same batch as Slashproof Business Plate: the same quest line, zone, vendor or reward set.