When Ape Training sent me their yoga block with rollers I had to try it immediately! I love how it all fits together, I find rollers always, well, roll out of sight and under my sofa after use ​ There are many benefits of rolling. The spikes really get into my erector muscles and I love (in a masochistic way!) how it relaxes them. The small ball is great for foot rolling too. ​ If you want to use the block as a block then you have to constantly be aware of what side you're us