Rigid gas permeable contact lenses are generally made of harder plastic materials that do not contain water. Although they are not as flexible as soft contact lenses, rigid gas permeable lenses allow more oxygen to pass through to the cornea than do soft lenses. This reduces the risk of corneal irritations.
Rigid gas permeable lenses can correct a wide range of vision problems, including astigmatism, which is a type of blurred vision caused by an irregularly shaped cornea. Users tend to take a little longer to adapt to these lenses. Rigid gas permeable lenses are easy to care for and more durable than soft lenses. They do not need to be replaced as frequently as soft contact lenses, and may be worn on average, for two to three years.