In The Burning Crusade it is item level 115, requires level 70 and sells to vendors for 3g 44s 79c. In Wrath of the Lich King it is item level 258, requires level 80 and sells to vendors for 3g 44s 79c. In MoP Classic it is item level 115, requires level 70 and sells to vendors for 4g 4s 56c.
Read from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
How Gloves of Centering Compares
Who It Suits
Mail is the armor type Evoker, Hunter and Shaman wear. With Agility or Intellect, Gloves of Centering suits Beast Mastery, Marksmanship and Survival Hunter; Elemental, Enhancement and Restoration Shaman; Devastation, Preservation and Augmentation Evoker.
Similar Items
The 10 items nearest to Gloves of Centering (item level 32) in item level among Armor > Mail, Hands slot, from item level 28 to 35.
Blizzard numbers items as they are created, so the named items next to ID 28520 (28515 to 28525) were usually added in the same batch as Gloves of Centering: the same quest line, zone, vendor or reward set.