Artifacts from the National Museum of American History's exhibit September 11: Remembrance and Reflection.
One of the least popular pieces of security equipment since the Sept. 11 terrorist attacks is now part of the Smithsonian's collection at the National Museum of American History - a metal detector from the Transportation Security Administration.
On Thursday, the TSA donated the metal detector, along with a training figure used by air marshals and a shirt from the first official screener uniform.
The objects are among more than 50 items from New York City, the Pentagon and Shanksville, Pa., that went on view Saturday.
They are part of a special exhibit, "September 11: Remembrance and Reflection."
Other objects on view will be airplane fragments, a door from a crushed fire truck and a flight attendant's handbook from Flight 93.
Also on display is the personal beeper of Jonathan Briley, who was an audiovisual technician at the Windows on the World restaurant on the 106th and 107th floors of the North Tower. Briley has been tentatively identified as the subject of the disturbing, famous photo called "The Falling Man," taken on Sept. 11, 2001.
The exhibit opened Saturday, Sept. 3 and runs through Sept. 11.