And they has great stretch, not easy to deform, not easy to break.

Made with durable gel material, they help reduce heel pain and improve foot stability, making them ideal for daily wear and plantar care. Soft silicone gel for maximum comfort. Material: Silicone Gel.

Peel away the clear protective backing film from the bottom layer of the silicone heel cup. Press the insert firmly down into the heel cup of your shoe, keeping the thicker contours aligned with the back wall.