Pressure Suit, RX-4, Constant Volume


Display Status:

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Collection Item Summary:

This suit is the model RX-4 and is little changed from its predecessor. Litton began adapting its line of vacuum chambers suits first for the Air Force in 1955 and then for NASA in 1964. The Litton suits were articulated exoskeletons that maintained a constant volume through a full range of motion. The RX-4 was built to deomonstrate its compatiblity with the existing liquid cooling and personal life support systems that NASA used during Apollo missions. The suit is modular with magnesium/lithium alloys in the rotary seals, and electron-beam welding techniques which helped reduce the weight of this suit to 63 lbs from the 90 pound weight of previous models

These experimental suits were part of NASA's Advanced Extra-Vehicular Suits (AES) program. They could operate at higher pressure, thus reducing the time-consuming oxygen pre-breathing period before extra vehicular activities.

NASA transferred this suit to the Museum in 1976.

Collection Item Long Description:

Data Source

National Air and Space Museum

Restrictions & Rights

Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum


Credit Line

Transferred from NASA - Manned Spacecraft Center


  • Plastic, metal (aluminum)
  • other: plastic, aluminum, steel, neoprene-coated nylon, leather, phenolic resin, anodized aluminum, gold plating, natural rubber, foam, rubber (silicone)


Approximately: 75 inches long x 35 inches wide x 16 inches deep (190.5 x 88.9 x 40.64cm)

Country of Origin

United States of America



Inventory Number