HRR Colour Test, 20 plates

Colour test developed by Hardy, Rand an Rittler for screening and examination of congenital and acquired colour defects.
Symbols (circle, cross, triangle) allow?to administer the test with children and adults alike.
4 demonstration plates, 6 screening plates for testing of protan, deutan and tritan colour defects.
The subsequent 14 plates allow for diagnosis of the type and extent of the colour defect.