Description:Ideal for auto massage of the parallel lines of muscles in the neck and back, since the gap is gentle on vertebra and allows Duo Ball to treat hard to reach places. Available in blue, black and pink.Density 60 G/L. Length 17 cm, diameter 9 cm.Material: 100% Polypropylene FoamWashing instructions: Wash your roller using a damp cloth with mildly soapy water to wipe your foam roller and let it air dry. We do not recommend cleaning foam roller with any harsh chemicals. Avoid storage at extreme temperatures (above 90 degrees and below 32 degrees) and keep it out of direct sunlight.