The skirmisher tassets is pair of ranging tassets from the skirmisher armour. It is a rare prize from the Treasure Hunter. As it has combat stats, Diango charges a fee of 50,000 coins to recover it after being destroyed. At the fifth tier, Black Dragonhide Chaps have slightly better combat bonuses, but weigh significantly more.
To change the tier of a piece of equipment, it must be in your inventory and not worn; then right-click it and select the Change option.