These refractometers offer exceptional optical design and improved image resolution with high contrast for easy viewing of scales. All reflection-coated glass optical components, including a 7x eyepiece, have been developed to improve illumination and shadowline contrast. Black housing improves image quality by reducing stray light. Optics and instrument scales are sealed inside, safe from harsh external conditions. Measure concentration of fruits, beverages, and canned goods; total solid content of syrups, vinegar, and sauces; or check the quality of vegetable, fruit, and grass tissues.