CUSTOM COMFORT AND HEIGHT. These multi-functional gel inserts allow you to build your own comfort and height. Ideal for anyone with one leg shorter than the other, the interlocking heel supports let you adjust the height of each insole. Different leg lengths can aggravate sciatica and hip or knee pain. Also great for heel pain or for anyone who simply wants to look taller. Set of 8 inserts adjust from .25” to 1.25”.