There are 16-18 oysters in a pound. The meaning of the number of heads is generally used to define the meaning of a catty how many (how many), so oysters 16-18 head is representative of a catty of oysters have 16-18, this way it can be convenient for customers to make clear how many quantities of oysters can be purchased by the customer to buy a catty of oysters. Oysters 16-18 head if the specifications of a catty, indicating that it is a medium-sized oysters, if it is a large oysters, then a catty is 10 specifications.