McKesson Round Handle Cane, Aluminum, Height Adjustable, Foam Grip, 1 Case of 6 Glove Box Holder Accepted by leading authorities as reducing the risk of 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 four tape tabs and a blue dryness strip for optimum skin protection The molded rubber tip supplies the aluminum walking cane with balance and firm footing Supports up to 300 pounds