Combat androids, also known as combat synthetics, are specially armored and hardened synthetics constructed specifically for combat purposes. Although the equipping of androids with weapons or uninhibited combat abilities was prohibited by the Geneva Convention, combat models have been widely employed by the Weyland-Yutani Corporation, who often used illegally manufactured units for security at critical Weyland-Yutani installations. Relaxing of regulations later also led to the use of combat androids by the United States Colonial Marine Corps.