Nightstar Silicone material is lightweight soft safe non-toxic and harmless to your feet. How to use: Clean your feet soak your feet in hot water for about half an hour Applying moisturizer evenly Put on silicone socks. Preventing and repairing cracking or peeling. The comfortable gel heel cups can be worn in most shoe styles including athletic shoes dress shoes with or without socks. You can highly use it for sporting activities especially where impact shock reduction is required provides amazing support and comfort to your feet. Very useful for any standing or walking activity. It can be easily washed by hand with a mild detergent when necessary.