This tether umbilical cord was used to connect astronaut Ed White to the Gemini 4 capsule during his historic "walk in space" in June 1965, which was the first time an American astronaut left the confines of the capsule.
It is constructed of a nylon layer covered with a heat-treated gold layer (to prevent peeling), which contained a 1/2 inch flat nylon tether, a silicone rubber oxygen hose and four electrical connectors and one communications lead. It is 23.5 feet long with an exterior diameter of 2 inches. It has a tensile strength of 350 pounds, while the tether has a tensile strength of 1,000 pounds. It was connected to the right hand side of the capsule with the other end attached to the "D" ring of the parachute harness.
NASA transferred this to the Museum in 1967.
This object is on display in Destination Moon at the National Air and Space Museum in Washington, DC.