What is the purpose of the series of numbers engraved on the table tennis butterfly board? How to identify a good board? Why are some carbon-added ones more expensive than pure wood ones?

In fact, each butterfly blade has a string of independent numbers on the lower right side of the board. This string of numbers represents: year of production and factory batch number. Therefore, the numbers on each blade are different... Carbon The board is more expensive than pure wood board. Because the process of producing carbon board is more complicated than that of pure wood. Carbon fiber is added during the plying process to make the bottom board harder and lighter. There are also synthetic bottom boards of aryl spruce. However, carbon fiber boards are more expensive than pure wood boards. It depends on what kind of pure wood racquet it is made of. Japan’s pure cypress racquet is the most advanced pure wood racquet.