Marksman's Crest is an Elite Gear Set. Set pieces can be bought directly from the Elite Gear Vendors using Alliance Points, and they are also available via "Rewards for the Worthy" mails by participating in PvP. Pieces are Abah's Watch Style in Medium Armor.
2 items: Adds 3-129 Stamina Recovery
3 items: Adds 3-129 Stamina Recovery
4 items: Adds 3-129 Weapon Damage
5 items: Reduces the cost of your Stamina abilities by 5% and increases the damage of your Bow abilities against players by 8%.
The set consists of medium armor and jewelry in all slots and a bow (no melee weapons, shields, or staves).