The 105mm cannon is used only by the Eurasian Dynasty. It is a direct-fire weapon which deals high damage to other units and fair damage to buildings, and due to being a ballistic weapon, ignores shields. Additionally, the 105mm cannon can only be used on one unit - the TT-100 Pamir - but can be mounted on any building with a Large weapon hardpoint. It has four ammunition upgrades, and one direct upgrade (the Twin 105mm Cannons).
It is required to develop the 120mm Cannon.