Qiang (3.5e Equipment)
From D&D Wiki
A Qiang is a double weapon. You can fight with it as if fighting with two weapons, but if you do, you incur all the normal attack penalties associated with fighting with two weapons, just as if you were using a one-handed weapon and a light weapon. A creature wielding a qiang in one hand can’t use it as a double weapon—only one end of the weapon can be used in any given round. The first head of the Qiang (the one dealing more damages) deal piercing damages, while the second deal bludgeoning damages.
The quarterstaff is a special monk weapon. This designation gives a monk wielding a Qiang special options. Additionally the Qiang, can be affected by weapon finesse as if it was a light weapon. If a Qiang is used as a two-handed it is treated as if it was a spear.