These are, in fact, the real hands of a gentleman who has the condition known as polydactyly.
Polydactyly describes when an extra digit develops on the hands or the feet and occurs in around 1 in 500 births.
This pair of hands belong to a man who brought his ill daughter to the doctor, says Daily Mail.
The doctor then noticed the man's extra digit and took a photo, sharing it to the medical app Figure 1 where medical professionals discuss cases they have come across.
While polydactyly isn't necessarily rare, it is very unusual so see a fully-developed extra digit.
Most instances of polydactyly result in smaller tissue masses, known as nubbins, and are easily removed by tying the affected area off to starve it of blood flow and then the extra tissue falls away. This is similar to how skin tags are treated.
When the extra digit is functioning, some people may decide to have it removed for cosmetic reasons. Other people may leave it as this man did.
Polydactyly is believed to be 50% inheritable, so if someone in your family has had an extra digit grow there's a chance there will be more!