FLEXIBLE BIG SPIKES --- This updated foot roller is equipped with flexible spikes and circular bead, which can not only make acupressure effect deep-tissue massage to comfort tired feet, or relief the arch pain relief from plantar fasciitis, but also friendly to some sensitive feet (NOTE: it's better you use it after doctors' consultation if you have the severe fasciitis or other serious foot disease; self-massage kit is no substitute for professional medical treatment) DEEP-TISSUE MASSAGE --- These massage balls and muscle roller are designed to release tight and uncomfortable muscles, relieve fasciitis, muscle soreness. They are also helpful to increase blood circulation and boost metabolism PORTABLE --- They are all small in size: balls' diameters are 2in and 2.6in, and the size of roller is 6.5x3x3in. It comes with a for convenient storage and taking along. You could take these massagers to many places such as gym, park, playground, hotel, classroom etc. SUPERIOR MATERIAL --- They are made of non-toxic, environmental friendly PVC and TPE material, insuring skin-friendly, durable, easy-to-clean and odor-free use experience WIDE USE --- This self-massage kit can be used by a variety of people, such as ballet dancers, teachers, field workers, nurses, athletes, children, runners, etc.