A low contrast test is a special way to measure visual acuity; determining how well eyes function in low light situations and/or being able to distinguish objects from similarly colored or shaded backgrounds. Testing is identical to the measurement of visual acuity at high contrast level. The 2.5% test is the most practical test in clinical use. Available in 5 contrast levels: 1.25%, 2.5%, 5%, 10%, and 25%. This chart is to be used in an ESV1200 or Model A+ illuminated cabinet. Includes recording forms and instructions.