This item is acquired in-game. See its sources below.
An Uncommon Cloth Wrist, item level 40, binds when picked up.
First seen in build 12.0.7.68887 (Midnight (patch 12.0.7)).
In the Appearances collection, Steamburst Wristwraps is listed as Quest. Appearance ID: 21972. 4 other items wear the same appearance:
Read from the World of Warcraft client build files.
3 quests list Steamburst Wristwraps among their rewards in Blizzard's quest data.
Foundry-Fired Plate Wristwraps, 
Wildwood Wrangler Wristwraps, 
Overgrowth Cutter WristwrapsFoundry-Fired Plate Wristwraps, Wildwood Wrangler Wristwraps, Overgrowth Cutter WristwrapsFoundry-Fired Plate Wristwraps, Wildwood Wrangler Wristwraps, Overgrowth Cutter WristwrapsRead from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
Cloth is the armor type Mage, Priest and Warlock wear. With Intellect, Steamburst Wristwraps suits Discipline, Holy and Shadow Priest; Arcane, Fire and Frost Mage; Affliction, Demonology and Destruction Warlock.
Built from the World of Warcraft client build files and recorded Auction House snapshots.
Steamburst Wristwraps uses icon file 937856, which 17 other items also use. The 3 closest by item ID:
Karabor Sage Wristwraps ID 113233 · Armor - Cloth · item level 40Firefly Bracers ID 114247 · Armor - Cloth · item level 43Agurak Wristwraps ID 117510 · Armor - Cloth · item level 40Blizzard numbers items as they are created, so the named items next to ID 112616 (112611 to 112623) were usually added in the same batch as Steamburst Wristwraps: the same quest line, zone, vendor or reward set.
Wildwood Wrangler Monnion ID 112611 · Armor - Mail · item level 40
Foundry-Fired Plate Girdle ID 112612 · Armor - Plate · item level 40
Steamburst Cord ID 112613 · Armor - Cloth · item level 40
Wildwood Wrangler Belt ID 112614 · Armor - Mail · item level 40
Overgrowth Cutter Belt ID 112615 · Armor - Leather · item level 40Foundry-Fired Plate Wristwraps ID 112617 · Armor - Plate · item level 40Wildwood Wrangler Wristwraps ID 112618 · Armor - Mail · item level 40Overgrowth Cutter Wristwraps ID 112619 · Armor - Leather · item level 40
Shagor's Collar ID 112620 · Quest "This thing's almost bigger than you."
Pack of Fishing Supplies ID 112623 · Miscellaneous · item level 5The raw ItemSparse values for item 112616 in the current client build.
Read from the World of Warcraft client build files: Item, ItemSparse, Lock, Holidays, AreaTable and CollectableSourceVendor.
TheWoWDB
