One Red Maddox Lens and one Green Maddox Lens are included. The Small Red and Green Maddox lenses are used to measure ocular torsion. The two Maddox lenses fit easily into a trial lens frame or holder. After a light fixation target is held up in front of the patient, the patient can rotate the lenses until both lines are parallel to the ground. This provides a measure of the patient’s ocular torsion.