Durometer
Durometer is a measure of relative stiffness and is used to compare polymers.
Sorbothane is softer than rubber and most other polymers. Sorbothane is measured on the Shore '00' scale.
Most types of rubber and other polymers are specified using the shore 'A' or Shore 'D' scales. In comparing stiffness, be aware of the scale being used for the material in question.
The softest Sorbothane, 30 durometer, is used for high frequency. highest damping and low temperature (less than -20 degree C). It has been described as having the consistency of wet chewing gum but with the memory of its original shape.
The 70 durometer Sorbothane is used for high performance isolation for low frequencies (less than 500 herz) or where material toughness is a key requirement.
50 durometer Sorbothane is a compromise in strength and isolation with high damping.
The stiffness comparison values in the attached chart are approximate and should be used only as a guide