Primal Gladiator's Linked Armor is part of the transmog set Primal Gladiator's Ringmail Armor (Shaman only), which the Appearances collection lists in 2 versions. The other 16 pieces:
Items Numbered Next to Primal Gladiator's Linked Armor
Blizzard numbers items as they are created, so the named items next to ID 115936 (115931 to 115941) were usually added in the same batch as Primal Gladiator's Linked Armor: the same quest line, zone, vendor or reward set.