For centuries yoga has been practiced on grass, hard dirt, or tiger skins; it wasn't until recently that yogis began to use specific mats. Today they prevent slipping in yoga studios. Mats also provide much-deserved comfort during Shavasana (lying flat on your back) at the end of your Hatha practice.Dimensions: 4.25 X 1.25 X 1.25 (HxLxW)