There is a brand of nail polish marketed to not just men, but manly men.

The company that makes it is called Alpha Nail. The company believes they can sell the nail polish by talking up the psychological benefits of wearing this polish. The psychological side of it describes how women are more attracted to men that stand out from the crowd instead of fitting in. 

They describe this product as being the way to stand out in a confident way. Their product stands out because of the formula that also strengthens your nails and it is easy to remove. Many famous guys use it including Johnny Depp, Prince Harry, Dave Navarro, David Beckham, amongst others including fighters and other celebrities. Would you use nail polish, especially when you are about to fight someone? Tell us your thoughts in the comments! 

(Source)