In Wrath of the Lich King it is item level 245 and requires level 80. In MoP Classic it is item level 225, requires level 80 and sells to vendors for 1c.
Read from the World of Warcraft client build files.
How Valorous Siegebreaker Shoulderplates Compares
Who It Suits
Plate is the armor type Death Knight, Paladin and Warrior wear. With Strength or Intellect, Valorous Siegebreaker Shoulderplates suits Arms, Fury and Protection Warrior; Holy, Protection and Retribution Paladin; Blood, Frost and Unholy Death Knight.
Transmog Sets
Valorous Siegebreaker Shoulderplates is part of the transmog set Valorous Siegebreaker Battlegear (Warrior only). The other 16 pieces:
Items Numbered Next to Valorous Siegebreaker Shoulderplates
Blizzard numbers items as they are created, so the named items next to ID 45433 (45428 to 45438) were usually added in the same batch as Valorous Siegebreaker Shoulderplates: the same quest line, zone, vendor or reward set.