LTTPs do have a limited shelf life as these materials are made from organic components that are vulnerable to environmental factors. UV rays, heat and humidity, bacteria and germs can all have a negative effect on the thermoplastic material causing breakdown. Always store your splinting materials flat in a dry, dark place for maximum benefit. Each product will have a label declaring the expiration date which is typically three years. If your product has been sitting on the shelf for longer than 3 years, it may not perform as expected. It may become brittle, discolored and overly stretchy.