The Kellan Capsulorhexis Marker – 5.5mm is a specialized tool used in cataract surgery to help create a precise capsulorhexis (a circular opening in the anterior capsule of the lens). The 5.5mm diameter marker provides an accurate and reproducible guide for surgeons to make a controlled, circular opening that is essential for the successful removal of the cataract and the insertion of an intraocular lens (IOL).