AT (stands for Auto Trooper) A01 was basic humanoid-shaped droid design which was used as a template for production of various droid models - both for military and civilian purposes - by different droid manufacturers. Full production ID for this design was droid.assassin_droid.autotrooper_a01. Like most humanoid-shaped models, it allowed to install wide array of the internal weapons and protective shileds, to complement its abilitiy to use most blasters, rifles and melee weapons.
With a few known exceptions, this droid design was used exclusively by the Sith Empire.

Variations

Operator	Planet / Event	Modification	Weapons	Comment	Size
Sith Empire	Tatooine Tatooine Planet	Imperial Attacker Droid	H1.a1.1 Electroblade H1 Heavy Electroblade Weapon Melee Weapons
	Corellia Corellia Planet	Imperial Booster Droid	L7.a3.4 Blaster Rifle L7 Rifle Weapon Blaster Rifles
		Imperial Tox-Droid	L5.a3.1 Electroblade L5 Electroblade Weapon Melee Weapons
		Imperial Chem-Droid	H1.a3.1 Heavy Blaster Pistol H1 Heavy Blaster Weapon Blaster Pistols
			L5.a3.1 Electroblade L5 Electroblade Weapon Melee Weapons
		Imperial Bio-Warfare Droid	H3.a3.4 Assault Cannon H3 Heavy Assault Cannon Weapon Assault Cannons
			L5.a3.1 Electroblade L5 Electroblade Weapon Melee Weapons
	Quesh Quesh Planet	Imperial Processing Droid	H3.a1.1 Heavy Blaster Rifle H3 Heavy Rifle Weapon Blaster Rifles
		Imperial Assembly Droid
	Esseles incident Esseles incident Event Cold War (3653BBY - 3642BBY)	Imperial Sabotage Drone	H1.a1.1 Heavy Blaster Pistol H1 Heavy Blaster Weapon Blaster Pistols	Wrist-mounted laser and shiled probe
		Imperial Auto Trooper	L7.a1.4 Rifle L7 Rifle Weapon Blaster Rifles
	Coruscant Coruscant Planet	Imperial Assault Droid	L7.a1.4 Rifle L7 Rifle Weapon Blaster Rifles	Explosive rounds, electro darts, wrist-mounted laser	x1.0
			L5.a1.1 Electroblade L5 Electroblade Weapon Melee Weapons
		Imperial Scout Droid	H1.a1.1 Heavy Blaster Pistol H1 Heavy Blaster Weapon Blaster Pistols	Toxic and sleep darts, poisoned blade	x1.2
			L5.a1.1 Electroblade L5 Electroblade Weapon Melee Weapons
		Imperial Seeker Droid	L5.a1.1 Electroblade L5 Electroblade Weapon Melee Weapons	Armor shield, charged plating, holo decoys, retractable blade	x1.2