Here is the blurb right from the site:
AXIS Roller Black – Round 36 x 6
Geared for moderate to heavy users, the exclusive AXIS™ Rollers give all the benefits of traditional rollers without breaking down. The AXIS’s, black, molded foam technology is firm in density, has a smooth surface, and will not lose its shape after moderate to heavy use. Fitness and rehab professionals will love the durability and lasting power of this roller.
— OPTP Website
This foam roller has survived my daily use and travels for the past two years and does the work equivalent to having a massage-therapist full-time on your staff for a fraction of a percentage of the price!