Stone and wood materials are healthy, hygienic, beneficial, non-toxic, easy to clean, free of sulfur, aniline or other toxins, and no side effects. The scientifically arranged various stones are rich in trace elements, which can effectively care for the feet, promote blood circulation, and effectively detoxify. It can soothe and activate veins, relax nerves and muscles, and eliminate fatigue. Can release body static electricity, maintain nerve and blood pressure function. Can relieve tension and promote sleep. Product DescriptionColor: as shown in the pictureSpecification: Material: EVA+stone+woodAvailable colors: red, blackThickness: approx. 2.8 cm/1.1 inchesWeight: 365-429gType: MassagerAvailable sizes: 36 (CN), 37 (CN), 39 (CN), 41 (CN), 42 (CN), 43 (CN)Package includes: 1 x pair of massage slippersNotes: It is normal that you may feel pain the first time you use it, so you can wear socks during use. The pain will be relieved after 15 days, and it can be worn barefoot for better results. It is recommended to drink 200-300ml warm water after use for 10 minutes each time.