An Antiques Roadshow guest was left gobsmacked when expert Ben Wright told him much his watch was worth after he traded it in his local pub.
The man explained how he had originally owned a cheap Rolex from Singapore, but decided to swap it with a pub landlord.
BBC star Ben said: "This is a military wristwatch, Second World War, by Longines and I'm looking at you and I don't think you're old enough to be in the Second World War."
The guest explained: "No, I actually acquired that by one of my friends who was travelling around the world and he was going through Singapore airport and I gave him £25 and said, 'Could you bring me back a solid gold diamond Rolex?'
"He said, 'Of course, I can.' So he came back with this sparkly diamond Rolex, about £20 worth, which I put on and it looked terrible."
The guest went on to reveal how he went to the pub 30 years ago, where the watch caught the eye of the landlord.
"The landlord goes, 'That is wonderful. Do you want to sell it?'
"I said, 'I don't want to sell it, I just got it.' So he asked, 'Would you swap it for this watch?'
"I hummed on it and gave him the watch and he in place gave me that watch and that's all I know about it."
Ben said: "Well, this watch by Longines is what some people call dirty dozen, which is a group of watchmakers who supplied the British Army with wristwatches."
He continued: "This particular one is by Longines and we know it is military, firstly because it's got the military crow's foot on the dial but also on the back of it, we have the crow's foot again.
"But we also have WWW, which is the acronym for wristwatch waterproof, which is what all military wristwatches were given right the way through to the 60s and 70s and maybe even now today."
He added: "It's in super condition and it's around 1944, 1945, there were luminous dots on it and luminous hands.
"This fortunately, the radium of this has disappeared now so you're not going to die of radium poisoning but it really must be handled with care.
"It's always a good idea to get some specialist advice. So, what are we going to pay for it at auction?
"So we had your dodgy Rolex, probably worth about £10 now. What are we thinking? £3,000-£4,000. You did well."
The guest was clearly shocked as he exclaimed: "No! No, you're joking. Never in a million years."
He said he would have been "over the moon" with just £500 or £600 and was astonished to find out the "unbelievable" value.
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