Beastie® Series products expand the RumbleRoller experience to provide more intense, versatile, portable, and affordable massage options. The Beastie is an aggressive massage ball that is the heart of this series. If you plan to work your entire body and experiment with different techniques, you will want to own both versions. Includes:(1) Original CLEAR Beastie without base Has firm but flexible bumps and recommended to be used on the floor and putting your full weight on it. (1) X-Firm GREEN Beastie without base Extremely firm and recommended to be used against a wall, where you'll be applying much lower forces to it. Beasties Series products don't replace the RumbleRoller, but they are more specific in purpose. Use them to dig deeper into a troublesome area, or to work with greater detail on smaller muscles, like those of the forearms and calves. Limitations of Conventional Massage BallsThe Beastie was created to overcome the many limitations of conventional massage balls: Too BigToo SmallToo HardToo SoftToo AbsorbentToo ShallowToo CrowdedToo SparseAdvantages of the BeastieWe wanted you to have not just a great massage ball, but the best possible massage ball. So we invested considerable time, attention, and resources in its development. Additional AccessoriesThe Beastie is also designed to work with the Beastie HookBeastie InstructionEach Beastie comes with a User's Guide that provides a very limited introduction to self-massage. For more advanced and detailed instruction, we recommend the DVD titled Jeff Alexander's SMR Tips for RumbleRoller and RR Beastie.