The mechno-arm was the custom-made prosthetic limb constructed for Anakin Skywalker after his right arm was severed by Count Dooku on Geonosis in 22 BBY. This prosthetic replacement was far stronger than the original.
On Geonosis, Anakin’s right arm was severed at the elbow by Dooku’s lightsaber. Anakin survived his encounter with the Sith Lord, and returned to Coruscant to recuperate and oversee the creation of a prosthetic limb. This robotic appendage lacked the synthskin applied to some models, and had a skeletal, droid-like appearance; it was designed to be a sturdy replacement, not a cosmetic disguise. Anakin’s new arm connected to the remainder of his limb via a synth-net neural interface, a complicated piece of technology that allowed Anakin to register feeling in his mechno-arm.
Anakin’s metal mechno-arm was an advanced version, featuring golden, electrostatic fingertips that simulated a sense of touch. Data collected by the fingertips was transmitted through sensory impulse lines running down the fingers and into an interface module at the wrist. This module served as the junction between Anakin’s robotic hand and living flesh. The arm’s servos and sensors were controlled by a power cell near the thumb. The mechno-hand’s motorized knuckles provide Anakin with a crushing strength far beyond the Human norm.
During the Clone Wars, many of the Jedi Council believed that Anakin lost some of his Humanity because of his prosthetic replacement. Anakin, however, was well at ease with his mechno-arm, and tinkered with it as he did his starfighter. He added strengthened alloy ligaments and armored shielding to bulk up his spindly robotic arm, giving the appearance of a well-muscled arm to match the rest of his toned body, and covered it with a glove. During the skirmish on Nelvaan, Anakin’s mechno-arm was destroyed after his Force Grip destroyed the crystal from the Siphon generator used to power the Separatist base on the world. He had a replacement, which R2 quickly attached to Anakin.