Celstim 10 Lb box (2 5 Lb Containers) Oxygen Conserver Concentrators With detachable full arms & 4012SC With detachable full arms & ELR * Steel spoke wheels are strong and maintenance free * Carbon steel frame with TRIPLE coated chrome for an attractive chip proof maintainable finish * Reinforced steel gussets at all weight bearing points provide additional strength * Durable reinforced nylon upholstery * Extra large padded armrests provide comfort and support * Steel spoke wheels are strong and maintenance free * Precision sealed wheel bearings in front and rear ensure long lasting performance and reliability * Extra large heavy duty aluminum footplates provide maximum support are attractive and crack proof 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 2 Each 5 Lbs