Since we have explained the second pizzeria endo-skeleton we should bring in the first enderskelteon who is based off of the original animatronics. The endo-01 is the main structure for the original animatronics while having weaker durability than them since it does not have any armor. 

Physical appearance: Endo-01 is a bipedal humanoid robot composed of a thinner pipe-like structure for limbs and stomach. Its flat rectangular head consists of a movable mouth with teeth, and a pair of blue eyeballs. its design from the first game is simply, while sporting rectangular cube shaped fingers and two-toed feet. In the VR game, Endo-01 is tweaked with additional tubes around the head, a series of wiring connecting some parts around both sides, hands and feet(Comes with three toes each), made similar to the withered animatronics endoskeleton, and possess tiny red lens as seen without eyeballs.