Polyurethane is a polymer material that can be flexibly adjusted to meet a variety of soft and hard requirements. In general, the hardness of polyurethane is characterized by Shore hardness, in two types: Type A and Type D. A type for the relatively low hardness of the material, D-type for the relatively high hardness of the material. Hardness of more than 97A above the general recommendation with Shaw D expression. Shore D can also reflect the hard material puncture resistance.

The hardness of the polyurethane is in the range of less than 0A to 90D, which may be soft and soft as jelly, or as hard as a stone. Polyurethane hardness is generally common in the 80A, such as polyurethane sticks, stirring and so on.