Unique Massage Design: Knobs of different sizes are designed according to the acupuncture points on the soles of the feet of the human body, so that every single reflex point in your foot can be ideally addressed. By stimulating these reflex points, the supply to the nerves as well as the blood circulation are stimulated, will make your body healthier. SIZE: 40-41=shoes length 26 cm=suit for the feet length 23-25cm ❤ Please Note:If you are not sure about your size,measure your feet from heel to toe.Please find the below Material:Premium high-quality EVA rubber, well made slide slippers for mens womens Customer's Satisfaction Is Our Priority: We offer 100% no risk money-back guarantee if you’re not thrilled with your purchase for any reason. Just tell us and we will do our best to give you the most satisfactory solution.