Gentle Blue: Great as a starter product for people new to stretching or core training. Perfect for users who prefer a softer touch or who have less muscles tissue on their backs. If you're somebody who wants something more restorative or relaxing you're going to want the gentle beam.
Firm Green: Releases tension with stronger intensity as it is a more dense foam. Recommended if you have a lot of muscles tissue or are really active and muscular. Perfect for users who like a deep tissue massage and really want to feel like they are getting into those tight and tender spots. The Firm Beam can also be used for balance exercises and releasing tension in the feet.
Travel /Desk Firm: Designed for travel but can be used in an office chair or on the couch. Travel beam is only available in a FIRM foam density which is green.