The Neutral Density Filter Bar allows to easily measure afferent pupillary defects (APD) also called “diminished pupil reaction to light levels”. Provides the filter values: 0.3, 0.6, 0.9, 1.2, 1.5, 1.8 Density Log Units. Each filter is 1.5″ (38 mm) square with an overall bar size of 10″ by 1.5″ (25.3 cm by 3.8 cm).
470200 is 10″ by 1.5″ (25.3 cm by 3.8 cm).





