In Wrath of the Lich King it is item level 226, requires level 80 and is named Earthshatter Kilt. In MoP Classic it is item level 213 and requires level 80.
Read from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
How Valorous Earthshatter Kilt Compares
Who It Suits
Mail is the armor type Evoker, Hunter and Shaman wear. With Agility or Intellect, Valorous Earthshatter Kilt suits Beast Mastery, Marksmanship and Survival Hunter; Elemental, Enhancement and Restoration Shaman; Devastation, Preservation and Augmentation Evoker.
Transmog Sets
Valorous Earthshatter Kilt is part of the transmog set Valorous Earthshatter Regalia (Shaman only). The other 16 pieces:
Blizzard numbers items as they are created, so the named items next to ID 40517 (40512 to 40522) were usually added in the same batch as Valorous Earthshatter Kilt: the same quest line, zone, vendor or reward set.