皮手 = Pi Hand. Hand Pi = 手圆周率

In Chinese the Greek letter pi which  symbolizes  mathematical ratio that makes a circle is represented by

 "Pi" in Chinese can mean several things including the mythical creature Pixiu (Pi Yao or Pi Xiu ).

貔貅

You may see Pi Xiu referred to as Pi Yao which is its heavenly form, Pi Kan, its sea form or Pi Xiu in its earth form. All forms are believed to be fiercely loyal to their master and will protect your home, generate luck and wealth while driving away evil spirits from your house. 

 Pi Yao (Pi Xiu) is the mythical winged lion with the powerful abilities to ward off evil spirits. Pi Yao is also very loyal and obedient, which makes him a very popular personal feng shui charm found in bracelets, necklaces and keychains.

Not many feng shui enthusiasts are familiar with the use of Pi Yao, or Pi Xiu. This does not make the Pi Yao less powerful, though. In fact, the Pi Yao (Pi Xiu) is the only feng shui cure used in the flying stars school of feng shui to protect against a specific type of negative energy, called the Grand Duke (Tai Sui).

皮

"Pi" in Chinese

Also known as Tianlu or Bixie, Pixiu is one of the five auspicious animals in ancient Chinese mythology, the other four being the dragon, phoenix, tortoise, and Chinese unicorn. Pixiu is considered a wealth-bringing divine animal with a dragon's head, a horse's body and a unicorn's feet. 

The animal, capable of flying, looks like a lion and has gray fur.

Pixiu is fierce and powerful by nature. As such, it is in charge of patrolling duty in the sky to keep demons, ghosts, plagues and diseases at bay. It has a mouth but no anus, so it just swallows things inside without passing anything out. That's why it is regarded as a divine accumulator of wealth from all sides without letting anything out.
 
Like the dragon and the lion, Pixiu is also believed to be an animal capable of driving away the evil sprits of a particular place and bringing happiness and good luck. But unlike Chinese unicorn, Pixiu is an auspicious animal with a ferocious nature and fierce loyalty in protecting its master. It is considered a house-guarding animal with the ability to ward off evil spirits. That’s why many Chinese people wear jade ornaments shaped like a Pixiu.

Pi (Perforated Disk)

The Pi (pronounced 'bee'), being one of the earliest symbolic carvings, represented the sun or heaven. It was used as a device to communicate with the heavens as well as in other ritualistic ceremonies.  In later dynasties, the Pi was symbolic of power and authority - much of that power was thought to come through the essence of jade…as it is considered the stone of heaven.

Pi Kan is a deified spirit of a sage of the 12th century B.C.; he was punished by a wicked tyrant and condemned to death. His heart was then used as an illustration of intelligence; in ancient time the Chinese believed that it was the heart that contained the intellect of a person. Therefore the heart became the symbol for the “perforated disc” known as Pi.

This divinity is also known as the Star-god of Affluence and worshipped on the 20th day of the 7th moon mostly by poor people and gamblers. An inexhaustible casket full of gold and silver and other sources of wealth are associated with this much-adored deity.

手圆周率  
Hand Pi in Chinese