100% SATISFACTION GUARANTEE--Your results are our top priority. So if our product doesn’t work for you simply let us know and we'll give you a full refund. We're always here for any questions or concerns. Function: Height increase insoles help distribute weight off your heels and relieve heel pain like Achilles tendonitis, plantar fasciitis, heel spurs. Besides, it adds the height you need invisibly and would be a nice choice to even leg length discrepancy and deal with the pain it caused. Washable and Reusable: Made of medical grade silicone gel that cover with a sweat absorbing fabric, heel cushion pads is soft and comfortable. Silicone is washable and reusable. The insole is still very sticky after washing. How to Choose: [Large Size: Advised for most men & women, suitable for shoes with wide heel.] [Small Size: Advised for most women who have narrow feet or heel, suitable for narrow heel shoes like women sneaker. ] Usually the choice of size is determined by the inside width of the shoe or the width of your heel. This product is used on shoes, so we recommend measuring the width of the inside of the shoe and then choosing the large or samll size that is closest to your shoe. 5mm/10mm/15mmAdjustable Heel Lifte: PrettSole gel insoles have 3 layers of padding, each layer 5 mm high. The bottom of each layer is sticky and protected by clear plastic. You can use 1, 2 or 3 layers of invisible pads depending on your needs.