BX Elite Mercenary Droid

The BX Elite Mercenary Droid is an upgrade of the BX Commando Droid created by Baktoid Combat Automata.

Appearance
BX Elites resembled their Commando Droid Predecessors, but with a bulkier frame, and hip-mounted blasters.

History
The BX Elite was a late edition to the Separatist's line of military units. They were conceived as an upgraded version of the BX-series of Commando Droids. Each BX Elite came with two hip-mounted blasters, which could be used to deadly effect against enemies. They also had head-mounted communications transmitters that allowed them to communicate with Separatist warships. Lastly, their Heuristic processors allowed them to think independently. The BX Elite was used very late in the Clone Wars, until Emperor Palpatine gave the order to shut down all separatist machines. The BX Elites were then put on the open market. BX Elites found great use in Imperial Military garrisons, but they could also be used as security droids.

Trivia

 * This droid is based on an unnamed mercenary droid in Star Wars: Droids.

Source
The Essential Guide to Droids: Star Wars: Droids Edition