Ishihara 38 Plate Chart Book for Color Blindness Ultrasound Units Accessories 3 Minutes Automatic Power Saving Style:Pair (Left & Right) 3 Minutes Automatic Power Saving Device The SelectAir© Low Air Loss Mattress Replacement System is quiet portable lightweight cost effective and very reliable * If individuals require microclimate control then SelectAir Low Air Loss Systems are the solution * Helps manage microclimate of the skin and improve moisture dissipation * Firm Mattress Mode helps facilitate nursing care during dressing changes and repositioning of the individual * Upright Mode gives added support when the head of the bed is elevated * Foot pillow helps cushion the foot * The zippered cover is fluid resistant and vapor permeable * Specifications: *Medicare code: E0277 Group 2 Support Surfaces * Construction: Individual baffles divided into 3 sections: head seat and foot 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