Traditionally, pure gum rubber rheological properties are tested and certified using the well-known Mooney viscometer according to ISO 289. This test is, in most of the cases, used for polymer choice for a specific recipe. Most rubber technologists recognize that this method fails to provide compound flow behavior information, especially when comparing polymers of identical ML(1+4) from various sources. Money Stress Relaxation has improved polymer source discrimination but is not widely adopted by polymer users although an increasing number of polymer suppliers are now providing this characteristic.