Snail mucin is derived from the excretion of a snail. In many face masks, you will see that it is written on the labels as SSF or snail secretion filtration. The product is naturally created by snails in a way to protect themselves. It is one of the best products that is used in the Korean skincare regime followed by offering noticeable results. It is a substance that is secreted when the snail is undergoing too much stress.