S82-27594 (25 Feb 1982) --- Astronaut Bruce McCandless II models NASA?s extravehicular mobility unit (EMU) spacesuit for Shuttle and the backpack unit (called a manned maneuvering unit) that will give future STS crewmembers extended mobility in space. A forerunner version of the MMU?called an astronaut maneuvering unit?was tested internally on Skylab. The MMU will allow astronauts for the first time in history to move about in the vicinity of their spacecraft without being tethered to the ship. McCandless was giving a demonstration of the EMU/MMU in JSC?s laboratory support facility.