HRR/Amsler Combination Color Test. This combination HRR/Amsler Grid book for testing of acquired color vision defects is now easier than ever with two of the key tests combined in one book. The new HRR 4th edition is combined with a book of Amsler Charts, including Diagonals, Red Lines, and Subdivided Squares. The set also includes reversible occluding glasses. Intended use is for medical professionals to qualify and quantify patients for color vision deficiency.