The model is 3 1. The specifications and models of the oil seal are 3 1, the inner diameter of the oil seal is 3 1mm, 43 is the outer diameter of the oil seal 43mm, and 10.3 is the width of the oil seal10.3mm.. Function: isolate the parts that need lubrication from the output parts of transmission parts to prevent lubricating oil from leaking. Type: According to the structure, it can be divided into single lip skeleton oil seal and double lip skeleton oil seal. According to the type of skeleton, it can be divided into internal skeleton oil seal, exposed skeleton oil seal and assembled oil seal. According to working conditions, it can be divided into rotary skeleton oil seal and reciprocating skeleton oil seal.