These contact lenses maintain their shape and differ from soft lenses in size and stability. They are significantly smaller than soft lenses and float on the tear film produced by the eye. The “pool of tears” created underneath the contact lens ensures the lens can move around the eye easily and produces crisp and clear images when lenses have been properly fitted. RGP lenses are attractive for wearers since they are suitable for extended wear due to their high oxygen permeability. With optimal care, rigid gas permeable contact lenses can last for almost two years.