Health Slippers [Mega Oshi Fumippa] by AlphaX These slippers have a large, raised insole like a bamboo footrest to loosen stiffness in the soles of your feet and improve circulation. The "Guigui Insole" provides a strong, stimulating, and pleasantly painful sensation. The insole is firm. Size: Suitable for sizes: Approximately 23-25 cm Materials: Fabric: Polyester Filling/Sole: Polyethylene I tried them on once, but the strong stimulation was a bit too much for me, as I'm sensitive to pain, so I've been storing them at home. They are like new. Thank you for looking.