These Gel Heel Cups by Shoe Doctor® are made from an advanced shock absorbing Opti-Gel® that relieves heel and back pain. SIZE: Small or Large CONTENTS: 1 Pair ADDITIONAL INFO: This soft gel fits in to the heel of any shoe and cradles the heel for stability and comfort. Insert these Shoe Doctor Gel Heel Cups into the rear of your shoe cup side facing up. Ensure the cup is pushed hard up into the heel of your shoe before placing your foot in the shoe.