The B2 Super Battle Droid is the successor of the B1 Battle Droid. The super battle droid design incorporates many existing components from the standard battle droid, but packages them in a much sturdier shell. The droid's signal receptor and cognitive unit is built into its bulky upper chest. The droid's high center of gravity is balanced by programmed movement algorithms. Though the droid has a built-in weapon, it can use standard infantry rifles with its limited manipulators. The armoured monogrip hands have built-in signal emitters that trigger the firing mechanism on specialized blaster rifles, allowing the droids to squeeze off shots even though they lack fingers.
B2s are owned by the Trade Federation and rarely come into possesion of anyone outside of the organisation. This may be the reason why there are no notible B2 individuals within the galaxy.