==Durometer== The Durometer returns a dimensionless (or unitless) value that ranges from zero to 100. It measures hardness and is limited to use with rubbers and polymers. Wikipedia has an article on the Shore Durometer.

http://www.matweb.com/reference/shore-hardness.aspx

A durometer is an instrument that is used to measure hardness. Specifically, a durometer can be used to measure a material's resistance to indentation.

90 durometer

The Mohs scale of mineral hardness is named after Friedrich Mohs, who developed it.

The Rockwell scale of metal hardness is named after Hugh and Stanley Rockwell, who created the machine that measures it. Hugh and Stanley Rockwell aren't directly related to each other.

The Shore Durometer scale for measuring the hardness of elastomeric materials like rubber is named after Albert Shore, who invented the measuring device called the durometer.