It's important for all cushions to have a properly designed pre-contoured shape. That's why we cooperated with Georgia Tech to study anthropometrics. Axiom SP Visco has a properly designed pre-contoured shape, designed to provide increased immersion, allowing the trochanters to bear an effective load, widening the base of support, and reducing the load the Ischial Tuberosities must bear. The well also has two small areas where foam is removed under the Ischial Tuberosities to facilitate immersion.