Our judo mats provide a Shore A material density rating of 35-40. This rating is at the lower end of Shore A ratings for our foam mats, which range from 35 to 45. Martial arts that involve a large amount of groundwork, as well as grappling and throwing, work best with a Shore A density rating of 35 to 40. Our judo mats also work for other disciplines, including Jiu-Jitsu and MMA. The EVA foam included with the tiles offers enough firmness to allow athletes to push off from a stable surface. You won't have as many concerns over suffering rolled ankles with these firm tiles, as your feet won't sink deeply into the judo mats while working out. And the surface of the tiles provides enough grip to work well for those athletes working with bare feet. The 4cm judo mats provide good fall protection and work best for disciplines that involve groundwork and throwing, our judo mats have been fall-height tested to 1.7m.