IT'S the final answer to just what the average Scotsman is hiding under his kilt.
Doctors have calculated the length of a typical fellow's manhood - and found those north of the border are among the longest.
The research was undertaken by urologists in an attempt to establish the true meaning of average and small size to help patients with psychological issues. No doubt the finding that the Scots are second only to the French - ooh la la - when it comes to length at an average 5.6 inches will be uplifting news for many.
The findings have emerged in a scientific paper published last week by doctors from the Urology departments at the Western General Hospital, Edinburgh, and St John's Hospital, Livingston. The hospitals treat hundreds of men every year with problems including erectile dysfunction and were keen to establish a true norm to help reassure patients.
The team, led by urologist Dr Shahid Khan, state: "A man's self-esteem can be greatly affected by the perception of his own penile size. Most patients concerned with an inadequate size are physically normal but seek reassurance and validation of their sexual and fertility potential
"These patients can usually be reassured by sharing the relevant medical knowledge with them.
"The results of this study help to establish a reference range for male genital size in the UK, which should be helpful for urologists in counselling patients."
The doctors, writing in the British Journal of Urology International, took a range of measurements from 609 men and found that the average length, extended as far as would be comfortable, was 5.6 inches.
Other studies worldwide have found relatively smaller sizes and the Scots were second only to the French, who measure in at 6.5 inches. A previous study of men in England put them at just 5.1 inches. The measurements were bigger also than those from men in countries such as the US, Italy, Germany, Israel, Turkey, Korea, Iran, India and Greece.
The study is the biggest of its kind carried out in the UK and though it may help some men feel more reassured, psychologists said it won't be entirely helpful to everyone.
Dr Cynthia McVey, head of psychology at Glasgow Caledonian University, said: "People compare themselves to others all the time. Women compare boobs and bum sizes and men also compare themselves.
"If someone sees there's an average size and finds themselves wanting, they could be upset. Instead, they should be thinking how much fun they are to be with or that they are a nice person.
"I don't know if size matters, but if it affects a man's confidence it could affect his performance."
Ash Mosahebi, a consultant plastic surgeon at the Royal Free Hospital, London, and member of the British Association of Aesthetic Plastic Surgeons, said: "It's like anything else, some people get fixated by part of their body.It can be psychological disease or there can be a legitimate reason for it.
The typical man is likely to be content with it but there will be a spectrum of people. "I am not sure how helpful it is to have an average size. It's not size that matters it's how you use it."