What feature of the M119A3 enhances its mobility?

The feature that enhances the mobility of the M119A3 is its lightweight and towed design. This howitzer's construction allows it to be easily moved and transported, whether by vehicle or by hand, enabling rapid deployment in various terrains. The lightweight aspect ensures that it can be maneuvered more effectively than heavier artillery systems, which might require more extensive logistical support and time to reposition. Additionally, its towed design means that it can be hitched to trucks and other vehicles, making it more versatile for different operational contexts and enhancing its overall strategic mobility on the battlefield.

Heavy armor, large size, and fixed position characteristics do provide benefits in specific scenarios, like durability or stability during firing, but they do not contribute to the mobility that is pivotal for the M119A3's operational effectiveness.