Cured epoxy resins have a number of different properties. They are a very stable and durable material, suitable to build machines and structures with a long lifespan. Epoxies have also good mechanical properties, making them a hard material whilst retaining some intrinsic flexibility at the same time. Epoxies are also adhesives materials which can be used in many ways. Finally, both resins and hardeners can be stored for a long time if they are not mixed, which is why epoxies are also specified in do-it-yourself packages for experienced, safety-conscious users.