Ishihara 38 Plate Chart Book for Color Blindness A P P Pumps Pads Access Aneroid with large adult adult Style:1 Pair (Left & Right) Aneroid with large adult adult small adult and child print durable one piece cuff and zipper case * Innovative trigger release design for easy operation * Certified accuracy to Ò3 mmHg * Meets AAMI shock resistant standard for enhanced durability (30 ) * Laser engraved dial face for accuracy * Ruby jeweled movement for long life * Trigger deflation valve for smooth one finger operation * Latex free for safety * 15 year calibration warranty * 5v handles * It averages 120 minutes of on time between charging * It has the smallest diameter of any 3 Accepted by leading authorities as a simple and accurate method for discovering congenital color blindness and red green blindness each in two forms complete and incomplete * Includes four special plates for tests to determine the kind and degree of defect in color vision * Makes use of the peculiarity that in red green blindness blue and yellow appear remarkably bright compared with red and green * Color plates encased in specially designed album type books for ease of handling * Detailed instructions included