Twitter was left in stitches this week after a guy who claims to have learned the secret to identifying a keeper from well, not a keeper, posted a guide for his fellow men that can help them identify a "good girl" from a bad one, based on the colour, shape and length of their nails.

The Twitter user posted a video of the guide which consists of different pieces of information aimed at helping his "bros" finding out whether the girl they are with is worth the "investment" or not.

At the start of the video Rocky explains how his "bros" always ask him advice on knowing who is the right girl and that's when he got the bright idea to document this bros guide that he decided to call, Nails at first sight-Survival guide one-on-one.

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According to Honey, the guide that has since gone viral begins by explaining what the colour a woman chooses to wear means. According to Rocky, Nude colours are all a safe zone and guys can "sleep with their eyes closed, while black white and french nails are what he considers "cautious" colours because they could be either good or bad. "I don't know man, it's 50/50" he says.

Rocky then moves on to explain the danger zone colours which are green, yellow, orange and red. These are dangerous because "If she has the courage to get yellow nails, then she'll have the guts to chop off your balls," he says.

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After he issues a fair warning about these danger colours and advises his "bros" to get health insurance if they planning on dating or partying with girls who rock these colours, Rocky moves on to the meaning behind the different nail shapes.

According to him, the sharper the nails, the more dangerous the girl. "They are not sharp for no reason" he says in his video.

He details how the shape a women decides to get is based on her mood.

Accompanied by pictures of all the shapes he mentions, Rocky explains how mountain peaks, stiletto's and arrowheads are all worn by women who have a 70% chance of being violent and aggressive.

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Thereafter, Rocky moves on to explain the meanings behind the lengths of the nails starting off with regular ones, which he calls "basic". Apparently these girls love Sunday brunches, face masks and can't twerk to save their lives.

Up next is medium nails, which he describes as the woman who is unorganised and messy. He also goes on to say that these 'huns' are broke 70% of the time.

Lastly, Rocky explains to us all about the woman with the long nails who is sassiest of the bunch, loves tequila and Hennessy and is the ultimate heart breaker. He also mentions that she probably sells drugs. LOL.

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Twitter users were highly amused by Rocky's guide and swarmed his posts with comments and pictures of their nails. A lot of them even agreed with his observations, calling them accurate.

This users commented, "As a girl I can confirm this to be accurate".

Another commented "Wow this deserves to be published and studied around the world. So accurate!"

While others simply posted pictures of their own nail choices.

And while many Tweeps found this funny, no one seemed to care that Rocky was not only sexist but also stereotypical.

I mean, I've had every kind of length, shape and colour. What would that make me, Rocky?

What are your thoughts on this 'survival guide'? Share your thoughts with us here.

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