Litton Suit
Based on a Litton "constant-volume" concept of the so-called "hard suit" of early 1955, the Mark I Extravehicular and Lunar Surface Suit was tested during the 1958-1959 period for more than 600 hours at simulated altitudes exceeding 100 miles. The unique construction of this suit permitted almost a full range of body motions by the person wearing it. (U.S. Air Force photo)