The game's collection data lists Guardian Serpent Leggings as sold by a vendor NPC in Warspear.
Vendor
Zone
Map
Waypoint
Other items it sells
NPC #88569
Warspear
-
-
166
Vendor NPC, zone and position come from the client's collection source tables (CollectableSourceInfo and CollectableSourceVendorSparse); coordinates are the in-game map readout.
Build history
First seen in build 5.5.4.69585 (Mists of Pandaria).
Read from the World of Warcraft client build files.
How Guardian Serpent Leggings Compares
Who It Suits
Cloth is the armor type Mage, Priest and Warlock wear. With Intellect, Guardian Serpent Leggings suits Discipline, Holy and Shadow Priest; Arcane, Fire and Frost Mage; Affliction, Demonology and Destruction Warlock.
Similar Items
The 10 items nearest to Guardian Serpent Leggings (item level 40) in item level among Armor > Cloth, Legs slot, from item level 32 to 41.
3 other items in the current build are also called Guardian Serpent Leggings. 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 87121 (87116 to 87126) were usually added in the same batch as Guardian Serpent Leggings: the same quest line, zone, vendor or reward set.