File:STS-135 crew in front of the Raffaello MPLM.jpg

English: CAPE CANAVERAL, Fla. – Space shuttle Atlantis' STS-135 crew participates in a crew equipment interface test, or CEIT, in the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The purpose of CEIT is for flight crew members to become familiar with the hardware and tools they will work with in space. Standing in front of the Raffaello multi-purpose logistics module, which will be packed with supplies, logistics and spare parts for their mission to the International Space Station, are, from left, Commander Chris Ferguson, Mission Specialists Sandy Magnus and Rex Walheim, and Pilot Doug Hurley. STS-135 also will return a failed ammonia pump module on the Lightweight Multi-Purpose Experiment Support Structure Carrier, or LMC, to help NASA better understand the failure mechanism and improve pump designs for future systems. STS-135, targeted to launch June 28, will be the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program. For more information visit, http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html.