This seawater desalter kit is an example of the survival equipment used during Project Mercury, the first U.S. human spaceflight program. Between 1961 and 1963, six Mercury astronauts were launched in one-man capsules, two on suborbital trajectories and four into orbit. At the conclusion of their missions, their capsules parachuted into the ocean and they and their spacecraft were recoverd by U.S. Navy ships and helicopters. Astronauts also had to be prepared to make emergency landings all around the world, so they were equipped with survival aids in case it took recovery forces a long time to reach them. With this desalter kit, it was possible to convert seawater into drinkable water.

This item was probably not flown on a mission. In 1973 NASA transferred ownership to the Smithsonian.