Blood taken from Ronald Reagan in the aftermath of the 1981 assassination attempt on the president is currently up for auction.
The dried blood residue, contained within a five inch glass vial, is for sale through PFC Auctions, with bids closing on May 24.
John Hinckley Jr took six shots at the president as he left the Hilton hotel in Washington, DC on March 30, 1981.
Just one hit Reagan, ricocheting off the president's bullet proof vehicle as he attempted to get inside. The bullet lodged in his lung, just an inch from his heart.
After initially believing he had escaped harm, the extent of the injury soon became clear, and Reagan was rushed to George Washington University Hospital, arriving just four minutes after leaving the hotel.
Only the swift action of Reagan's bodyguards in covering the president and pushing him into his vehicle prevented him from a much worse fate.
The label on the vial states that the blood was extracted on the day of the assassination attempt. It is accompanied by a printed form detailing the president's particulars.
The provenance behind the piece is superb, coming from the son of one of the blood testers. Yet the consignor received a scare when he first contacted the Reagan National Library about selling the piece.
In a letter of provenance accompanying the vial, he describes how the federal agent he spoke to had to confer with a number of government agencies upon hearing that nature of the artefact.
"He called back in 25 minutes and said that everything was OK, National Archives was not interested in what I had, nor was the Secret Service, the FBI and other agencies," he writes.
Last month a piece of soil thought to contain Gandhi's blood from his assassination sold at auction for £10,000 ($15,940).
Reagan was the first US president to survive an assassination attempt by gunshot. He left hospital after 13 days.