The XP battledroid was invented by Fleet Admiral Fell Skyhawk himself, using parts from other various droids. The XP baattledroid has a specially designed head that, without plating, looks like a scull. On top of this can be placed various helmet-like plating that is specially designed to give the droid more visual abilities as well as other abilities for whatever task its owner wants it to do. The standard version comes with a helmet simmilar in design to a Phase I Clone Trooper helmet. The torso also has modular plating, however without plating it looks more like a 3PO unit without plating, or a BD-3000 without plating for female versions. The standard plating looks like clone trooper armor. The legs are IG-100 and YVH droid legs spliced together, and have no extra plating, but are painted white on the standard droid model. The arms use YVH droid and General Grevious robotic shell technologies. It can split into two parts with three fingers on each hand.
The XP's also have modular database devises so they can be made to function for different tasks. While they are battle droids, standard models have Class 3 droid understanding and AI activity. Different moduals can even get them too Class 1.
Fleet Admiral Fell Skyhawk's personal XP droid, XP-01,even has a special modual that allows it to use lightsabers.