A vibro-ax was a more powerful version of the standard axe.
A vibro-ax was a standard ax handle-fitted with a vibration generator and power cell, causing the ax head to vibrate rapidly, thus creating a vibroweapon. Vibroweapons had more cutting power with less effort from the wielder. Some handles were designed to dampen the vibration effect for the user, though cruder versions, such as Arg'garoks wielded by the Gamorreans, used wooden handles. These weapons were often left deactivated, simply to allow the user to show off their physical strength and to intimidate rivals, since these weapons were capable of easily decapitating most humanoid species with a single blow.
Variants of the vibro-ax included the Acidic Paragon vibro axe, which actually exuded acid, the sophisticated BD-1 Cutter vibro-ax, and the Clan Groogrun vibro-ax, which was another Gamorrean vibro-ax.
The vibro-axes were common in the underworld of the galaxy, and especially among Gamorrean warriors and guards, Togorian pirates, and other sorts of criminals. Force Adepts that lacked a lightsaber had been known to take up the vibro-ax and use their Force powers to enhance their combat abilities.
Jabba the Hutt's dim-witted Gammorean guards used vibro-axes, while his Weequay guards used the BD-1 Cutter vibro-ax model. During his infiltration into Jabba's Palace, Lando Calrissian used the BD-1 Cutter vibro-ax as his primary weapon.