Field Marshal's Battlegear is the Level 60 PvP Epic Set. It contains 6 pieces. Has set bonuses at 2, 3, and 6 pieces.
Field Marshal's Plate Armor
Field Marshal's Plate Helm
Field Marshal's Plate Shoulderguards
Marshal's Plate Boots
Marshal's Plate Gauntlets

Marshal's Plate Legguards

Set Bonuses
Wearing more pieces of this set will convey bonuses to your character.
2 pieces: +20 Stamina.
3 pieces: Reduces the cooldown of your Intercept ability by 5 sec.
6 pieces: +40 Attack Power.