Venom Snake's bionic arm

Big Boss, after losing his left arm between the XOF Trojan horse operation in March 1975 and awakening in the hospital nine years later, had his arm replaced with a myoelectric arm prosthesis shortly after escaping the hospital. The arm was specifically designed for Big Boss. It was red in color, although it could be customizable to include new gadgets and colors, including one that had an upgradable battery and could deliver 120 volts at will, enough to ensure an enemy was knocked unconscious.

Behind the scenes
The prosthetic hand made its debut in Metal Gear Solid V: The Phantom Pain. It resembled a similar prosthetic hand used by Vladimir Aleksandrovich Zadornov from Metal Gear Solid: Peace Walker.

"STUN ARM A myoelectric arm prosthetic designed specifically for Snake. Capable of delivering a high-voltage 120V electric shock to incapacitate targets. Upgradable battery"

- Stun Arm menu description in Metal Gear Solid V: The Phantom Pain