Wmicro Veterinarians and Clinicians Refractometer RHC-200ATC with 3-in-1 scale 1.Equipped with scale measurement which provides direct reading,Easy to focus and calibrate. 2.Uses ambient light only which means battery or power source is not required. 3.Heavy-duty and lightweight with its aluminum construction. 4.Cushioned with soft & comfortable non-slip rubber. 5.Durable and built to last long.