What weird souvenir does Ashton Kutcher keep with him?

The actor’s Two And A Half Men co-star Jon Cryer spilled the beans when they appeared on US chat show host Conan O’Brien’s programme.

Jon, 49, explained how he discovered Ashton’s odd possession: “In the very first episode that Ashton was in, there was a point at which he was supposed to drop his trousers and be completely naked in front of me.

“And we didn’t know how to do that in front of the live studio audience without him actually being naked, because the whole point was it was supposed to shock people. So we said we were going to have to cover him up somehow, but it still has to be shocking.

“We were working this over in the writer’s room, and then Ashton pipes in ‘Oh, well I’ve got a huge prosthetic penis in my trailer’. We all had that awkward moment of, ‘Of course you do’.”

Ashton – a new dad with fiancee Mila Kunis – joked: “Doesn’t everyone?”

Jon then explained that the prop was actually a person’s midsection with “a very impressive – anatomically correct member”, and Ashton laughed: “Listen, they only had one guy who was willing to be the mould…”

The star then went on to explain that the pretend penis was made as part of a hidden camera web short he was part of, where a man would parade around the streets in it.

“Who knows when you’re going to need a prosthetic penis? So I kept it!” said the 37-year-old.

The pair were being interviewed as their popular comedy series came to an end after 12 seasons.

Jon had starred in the show since it started while former Punk’d star Ashton replaced Charlie Sheen in 2011.

Before the finale aired he posted a message on Facebook singing Jon’s praises.

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